firebird-mirror/src/dsql/DdlNodes.epp

/*
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 * Adriano dos Santos Fernandes - refactored from pass1.cpp, ddl.cpp, dyn*.epp
 */

#include "firebird.h"
#include "dyn_consts.h"
#include "../jrd/common.h"
#include "../dsql/DdlNodes.h"
#include "../dsql/node.h"
#include "../jrd/blr.h"
#include "../jrd/btr.h"
#include "../jrd/dyn.h"
#include "../jrd/flags.h"
#include "../jrd/intl.h"
#include "../jrd/jrd.h"
#include "../jrd/msg_encode.h"
#include "../jrd/obj.h"
#include "../jrd/tra.h"
#include "../jrd/os/path_utils.h"
#include "../jrd/IntlManager.h"
#include "../jrd/PreparedStatement.h"
#include "../jrd/blb_proto.h"
#include "../jrd/cmp_proto.h"
#include "../jrd/dsc_proto.h"
#include "../jrd/dyn_dl_proto.h"
#include "../jrd/dyn_ut_proto.h"
#include "../jrd/exe_proto.h"
#include "../jrd/intl_proto.h"
#include "../jrd/isc_f_proto.h"
#include "../jrd/met_proto.h"
#include "../jrd/scl_proto.h"
#include "../jrd/vio_proto.h"
#include "../dsql/ddl_proto.h"
#include "../dsql/errd_proto.h"
#include "../dsql/gen_proto.h"
#include "../dsql/make_proto.h"
#include "../dsql/metd_proto.h"
#include "../dsql/pass1_proto.h"
#include "../common/StatusArg.h"

namespace Jrd {

using namespace Firebird;
using namespace Dsql;

static void checkForeignKeyTempScope(thread_db* tdbb, jrd_tra* transaction,
	const MetaName&	childRelName, const MetaName& masterIndexName);
static void checkSpTrigDependency(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName);
static void checkViewDependency(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName);
static void clearPermanentField(dsql_rel* relation, bool permanent);
static void deleteKeyConstraint(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& constraintName, const MetaName& indexName);
static bool fieldExists(thread_db* tdbb, jrd_tra* transaction, const MetaName& relationName,
	const MetaName& fieldName);
static void makeRelationScopeName(const MetaName& name, const rel_t type, string& message);
static void modifyLocalFieldPosition(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName, USHORT newPosition,
	USHORT existingPosition);
static rel_t relationType(SSHORT relationTypeNull, SSHORT relationType);
static void saveRelation(thread_db* tdbb, DsqlCompilerScratch* dsqlScratch,
	const dsql_str* relationName, bool creating);
static void updateRdbFields(const TypeClause& type,
	SSHORT& fieldType,
	SSHORT& fieldLength,
	SSHORT& fieldSubTypeNull, SSHORT& fieldSubType,
	SSHORT& fieldScaleNull, SSHORT& fieldScale,
	SSHORT& characterSetIdNull, SSHORT& characterSetId,
	SSHORT& characterLengthNull, SSHORT& characterLength,
	SSHORT& fieldPrecisionNull, SSHORT& fieldPrecision,
	SSHORT& collationIdNull, SSHORT& collationId,
	SSHORT& segmentLengthNull, SSHORT& segmentLength);

DATABASE DB = STATIC "ODS.RDB";


//----------------------


// Check temporary table reference rules between given child relation and master
// relation (owner of given PK/UK index).
static void checkForeignKeyTempScope(thread_db* tdbb, jrd_tra* transaction,
	const MetaName&	childRelName, const MetaName& masterIndexName)
{
	AutoCacheRequest request(tdbb, drq_l_rel_info, DYN_REQUESTS);
	bool error = false;
	string master, child;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		RLC_M IN RDB$RELATION_CONSTRAINTS CROSS
		REL_C IN RDB$RELATIONS CROSS
		REL_M IN RDB$RELATIONS
		WITH (RLC_M.RDB$CONSTRAINT_TYPE EQ UNIQUE_CNSTRT OR
			  RLC_M.RDB$CONSTRAINT_TYPE EQ PRIMARY_KEY) AND
			 RLC_M.RDB$INDEX_NAME EQ masterIndexName.c_str() AND
			 REL_C.RDB$RELATION_NAME EQ childRelName.c_str() AND
			 REL_M.RDB$RELATION_NAME EQ RLC_M.RDB$RELATION_NAME
	{
		const rel_t masterType = relationType(REL_M.RDB$RELATION_TYPE.NULL, REL_M.RDB$RELATION_TYPE);
		fb_assert(masterType == rel_persistent ||
				  masterType == rel_global_temp_preserve ||
				  masterType == rel_global_temp_delete);

		const rel_t childType = relationType(REL_C.RDB$RELATION_TYPE.NULL, REL_C.RDB$RELATION_TYPE);
		fb_assert(childType == rel_persistent ||
				  childType == rel_global_temp_preserve ||
				  childType == rel_global_temp_delete);

		error = masterType != childType &&
			!(masterType == rel_global_temp_preserve && childType == rel_global_temp_delete);

		if (error)
		{
			makeRelationScopeName(masterIndexName, masterType, master);
			makeRelationScopeName(childRelName, childType, child);
		}
	}
	END_FOR

	if (error)
	{
		// Msg 232 : "%s can't reference %s"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(232, DYN_MSG_FAC)) << child << master);
	}
}

// Check temporary table reference rules between just created child relation and all
// its master relations.
static void checkRelationTempScope(thread_db* tdbb, jrd_tra* transaction,
	const MetaName&	childRelName, const rel_t childType)
{
	if (childType != rel_persistent &&
		childType != rel_global_temp_preserve &&
		childType != rel_global_temp_delete)
	{
		return;
	}

	AutoCacheRequest request(tdbb, drq_l_rel_info2, DYN_REQUESTS);
	bool error = false;
	string master, child;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		RLC_C IN RDB$RELATION_CONSTRAINTS CROSS
		IND_C IN RDB$INDICES CROSS
		IND_M IN RDB$INDICES CROSS
		REL_M IN RDB$RELATIONS
		WITH RLC_C.RDB$CONSTRAINT_TYPE EQ FOREIGN_KEY AND
			 RLC_C.RDB$RELATION_NAME EQ childRelName.c_str() AND
			 IND_C.RDB$INDEX_NAME EQ RLC_C.RDB$INDEX_NAME AND
			 IND_M.RDB$INDEX_NAME EQ IND_C.RDB$FOREIGN_KEY AND
			 IND_M.RDB$RELATION_NAME EQ REL_M.RDB$RELATION_NAME
	{
		const rel_t masterType = relationType(REL_M.RDB$RELATION_TYPE.NULL, REL_M.RDB$RELATION_TYPE);
		fb_assert(masterType == rel_persistent ||
				  masterType == rel_global_temp_preserve ||
				  masterType == rel_global_temp_delete);

		error = masterType != childType &&
			!(masterType == rel_global_temp_preserve && childType == rel_global_temp_delete);

		if (error)
		{
			makeRelationScopeName(REL_M.RDB$RELATION_NAME, masterType, master);
			makeRelationScopeName(childRelName, childType, child);
		}
	}
	END_FOR

	if (error)
	{
		// Msg 232 : "%s can't reference %s"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(232, DYN_MSG_FAC)) << child << master);
	}
}

// Checks to see if the given field is referenced in a stored procedure or trigger.
// If the field is referenced, throw.
static void checkSpTrigDependency(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName)
{
	AutoRequest request;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FIRST 1
		DEP IN RDB$DEPENDENCIES
		WITH DEP.RDB$DEPENDED_ON_NAME EQ relationName.c_str() AND
			 DEP.RDB$FIELD_NAME EQ fieldName.c_str()
	{
		MetaName depName(DEP.RDB$DEPENDENT_NAME);

		// msg 206: Column %s from table %s is referenced in %s.
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(206, DYN_MSG_FAC)) << fieldName << relationName << depName);
	}
	END_FOR
}

// Checks to see if the given field is referenced in a view. If it is, throw.
static void checkViewDependency(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName)
{
	AutoRequest request;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FIRST 1
		X IN RDB$RELATION_FIELDS CROSS
		Y IN RDB$RELATION_FIELDS CROSS
		Z IN RDB$VIEW_RELATIONS
		WITH X.RDB$RELATION_NAME EQ relationName.c_str() AND
			 X.RDB$FIELD_NAME EQ fieldName.c_str() AND
			 X.RDB$FIELD_NAME EQ Y.RDB$BASE_FIELD AND
			 X.RDB$FIELD_SOURCE EQ Y.RDB$FIELD_SOURCE AND
			 Y.RDB$RELATION_NAME EQ Z.RDB$VIEW_NAME AND
			 X.RDB$RELATION_NAME EQ Z.RDB$RELATION_NAME AND
			 Y.RDB$VIEW_CONTEXT EQ Z.RDB$VIEW_CONTEXT
	{
		MetaName viewName(Z.RDB$VIEW_NAME);

		// msg 206: Column %s from table %s is referenced in  %s.
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(206, DYN_MSG_FAC)) << fieldName << relationName << viewName);
	}
	END_FOR
}

// Removes temporary pool pointers from field, stored in permanent cache.
static void clearPermanentField(dsql_rel* relation, bool permanent)
{
	if (relation && relation->rel_fields && permanent)
	{
		relation->rel_fields->fld_procedure = NULL;
		relation->rel_fields->fld_ranges = NULL;
		relation->rel_fields->fld_character_set = NULL;
		relation->rel_fields->fld_sub_type_name = NULL;
		relation->rel_fields->fld_relation = relation;
	}
}

// Delete a record from RDB$RELATION_CONSTRAINTS based on a constraint name.
//
//      On deleting from RDB$RELATION_CONSTRAINTS, 2 system triggers fire:
//
//      (A) pre delete trigger: pre_delete_constraint, will:
//
//        1. delete a record first from RDB$REF_CONSTRAINTS where
//           RDB$REF_CONSTRAINTS.RDB$CONSTRAINT_NAME =
//                               RDB$RELATION_CONSTRAINTS.RDB$CONSTRAINT_NAME
//
//      (B) post delete trigger: post_delete_constraint will:
//
//        1. also delete a record from RDB$INDICES where
//           RDB$INDICES.RDB$INDEX_NAME =
//                               RDB$RELATION_CONSTRAINTS.RDB$INDEX_NAME
//
//        2. also delete a record from RDB$INDEX_SEGMENTS where
//           RDB$INDEX_SEGMENTS.RDB$INDEX_NAME =
//                               RDB$RELATION_CONSTRAINTS.RDB$INDEX_NAME
static void deleteKeyConstraint(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& constraintName, const MetaName& indexName)
{
	SET_TDBB(tdbb);

	AutoCacheRequest request(tdbb, drq_e_rel_const, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		RC IN RDB$RELATION_CONSTRAINTS
		WITH RC.RDB$CONSTRAINT_NAME EQ constraintName.c_str() AND
			 RC.RDB$CONSTRAINT_TYPE EQ FOREIGN_KEY AND
			 RC.RDB$RELATION_NAME EQ relationName.c_str() AND
			 RC.RDB$INDEX_NAME EQ indexName.c_str()
	{
		found = true;
		ERASE RC;
	}
	END_FOR

	if (!found)
	{
		// msg 130: "CONSTRAINT %s does not exist."
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(130, DYN_MSG_FAC)) << constraintName);
	}
}

// Checks to see if the given field already exists in a relation.
static bool fieldExists(thread_db* tdbb, jrd_tra* transaction, const MetaName& relationName,
	const MetaName& fieldName)
{
	AutoRequest request;
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$RELATION_FIELDS
		WITH FLD.RDB$RELATION_NAME EQ relationName.c_str() AND
			 FLD.RDB$FIELD_NAME EQ fieldName.c_str()
	{
		found = true;
	}
	END_FOR

	return found;
}

// Make string with relation name and type of its temporary scope.
static void makeRelationScopeName(const MetaName& name, const rel_t type, string& message)
{
	const char* scope = NULL;

	if (type == rel_global_temp_preserve)
		scope = REL_SCOPE_GTT_PRESERVE;
	else if (type == rel_global_temp_delete)
		scope = REL_SCOPE_GTT_DELETE;
	else
		scope = REL_SCOPE_PERSISTENT;

	message.printf(scope, name.c_str());
}

// Alters the position of a field with respect to the
// other fields in the relation.  This will only affect
// the order in which the fields will be returned when either
// viewing the relation or performing select * from the relation.
//
// The rules of engagement are as follows:
//      if new_position > original position
//         increase RDB$FIELD_POSITION for all fields with RDB$FIELD_POSITION
//         between the new_position and existing position of the field
//      then update the position of the field being altered.
//         just update the position
//
//      if new_position < original position
//         decrease RDB$FIELD_POSITION for all fields with RDB$FIELD_POSITION
//         between the new_position and existing position of the field
//      then update the position of the field being altered.
//
//      if new_position == original_position -- no_op
static void modifyLocalFieldPosition(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName, USHORT newPosition,
	USHORT existingPosition)
{
	// Make sure that there are no duplicate field positions and no gaps in the position sequence.
	// (gaps are introduced when fields are removed)

	AutoRequest request;
	USHORT newPos = 0;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$RELATION_FIELDS
		WITH FLD.RDB$RELATION_NAME EQ relationName.c_str()
		SORTED BY ASCENDING FLD.RDB$FIELD_POSITION
	{
		if (FLD.RDB$FIELD_POSITION != newPos)
		{
			MODIFY FLD USING
				FLD.RDB$FIELD_POSITION = newPos;
			END_MODIFY
		}

		++newPos;
	}
	END_FOR

	// Find the position of the last field in the relation.
	SLONG maxPosition = -1;
	DYN_UTIL_generate_field_position(tdbb, NULL, relationName, &maxPosition);

	// If the existing position of the field is less than the new position of
	// the field, subtract 1 to move the fields to their new positions otherwise,
	// increase the value in RDB$FIELD_POSITION by one.

	bool moveDown = false;
	if (existingPosition < newPosition)
		moveDown = true;

	// Retrieve the records for the fields which have a position between the
	// existing field position and the new field position.

	request.reset();

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$RELATION_FIELDS
		WITH FLD.RDB$RELATION_NAME EQ relationName.c_str() AND
				FLD.RDB$FIELD_POSITION >= MIN(newPosition, existingPosition) AND
				FLD.RDB$FIELD_POSITION <= MAX(newPosition, existingPosition)
	{
		MODIFY FLD USING
			// If the field is the one we want, change the position, otherwise
			// increase the value of RDB$FIELD_POSITION.
			if (fieldName == FLD.RDB$FIELD_NAME)
			{
				if (newPosition > maxPosition)
				{
					// This prevents gaps in the position sequence of the fields.
					FLD.RDB$FIELD_POSITION = maxPosition;
				}
				else
					FLD.RDB$FIELD_POSITION = newPosition;
			}
			else
			{
				if (moveDown)
					FLD.RDB$FIELD_POSITION = FLD.RDB$FIELD_POSITION - 1;
				else
					FLD.RDB$FIELD_POSITION = FLD.RDB$FIELD_POSITION + 1;
			}

			FLD.RDB$FIELD_POSITION.NULL = FALSE;
		END_MODIFY
	}
	END_FOR
}

// Convert RDB$RELATION_TYPE to rel_t type.
static rel_t relationType(SSHORT relationTypeNull, SSHORT relationType)
{
	return relationTypeNull ? rel_persistent : rel_t(relationType);
}

// Save the name of the relation or view currently being defined. This is done to support definition
// of triggers which will depend on the metadata created in this statement.
static void saveRelation(thread_db* tdbb, DsqlCompilerScratch* dsqlScratch,
	const dsql_str* relationName, bool creating)
{
	//// TODO: Verify "creating" usage when using this function for views.

	DsqlCompiledStatement* statement = dsqlScratch->getStatement();

	if (dsqlScratch->flags & DsqlCompilerScratch::FLAG_METADATA_SAVED)
		return;

	dsqlScratch->flags |= DsqlCompilerScratch::FLAG_METADATA_SAVED;

	dsql_rel* relation;

	if (!creating)
		relation = METD_get_relation(dsqlScratch->getTransaction(), dsqlScratch, relationName);
	else
	{
		MemoryPool& pool = *tdbb->getDefaultPool();
		relation = FB_NEW(pool) dsql_rel(pool);
		relation->rel_name = relationName->str_data;
		relation->rel_flags = REL_creating;
	}

	dsqlScratch->relation = relation;
}

// Update RDB$FIELDS received by reference.
static void updateRdbFields(const TypeClause& type,
	SSHORT& fieldType,
	SSHORT& fieldLength,
	SSHORT& fieldSubTypeNull, SSHORT& fieldSubType,
	SSHORT& fieldScaleNull, SSHORT& fieldScale,
	SSHORT& characterSetIdNull, SSHORT& characterSetId,
	SSHORT& characterLengthNull, SSHORT& characterLength,
	SSHORT& fieldPrecisionNull, SSHORT& fieldPrecision,
	SSHORT& collationIdNull, SSHORT& collationId,
	SSHORT& segmentLengthNull, SSHORT& segmentLength)
{
	// Initialize all nullable fields.
	fieldSubTypeNull = fieldScaleNull = characterSetIdNull = characterLengthNull =
		fieldPrecisionNull = collationIdNull = segmentLengthNull = TRUE;

	if (type.type == dtype_blob)
	{
		fieldSubTypeNull = FALSE;
		fieldSubType = type.subType;

		fieldScaleNull = FALSE;
		fieldScale = 0;

		if (type.subType == isc_blob_text)
		{
			characterSetIdNull = FALSE;
			characterSetId = type.charSetId;

			collationIdNull = !type.collateSpecified;
			collationId = type.collationId;
		}

		if (type.segLength != 0)
		{
			segmentLengthNull = FALSE;
			segmentLength = type.segLength;
		}
	}
	else if (type.type <= dtype_any_text)
	{
		fieldSubTypeNull = FALSE;
		fieldSubType = type.subType;

		fieldScaleNull = FALSE;
		fieldScale = 0;

		characterLengthNull = FALSE;
		characterLength = type.charLength;

		characterSetIdNull = FALSE;
		characterSetId = type.charSetId;

		collationIdNull = !type.collateSpecified;
		collationId = type.collationId;
	}
	else
	{
		fieldScaleNull = FALSE;
		fieldScale = type.scale;

		if (DTYPE_IS_EXACT(type.type))
		{
			fieldPrecisionNull = FALSE;
			fieldPrecision = type.precision;

			fieldSubTypeNull = FALSE;
			fieldSubType = type.subType;
		}
	}

	if (type.type == dtype_varying)
	{
		fb_assert(type.length <= MAX_SSHORT);
		fieldLength = (SSHORT) (type.length - sizeof(USHORT));
	}
	else
		fieldLength = type.length;

	fieldType = blr_dtypes[type.type];
}


//----------------------


// Delete a security class.
bool DdlNode::deleteSecurityClass(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& secClass)
{
	AutoCacheRequest request(tdbb, drq_e_class, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		SC IN RDB$SECURITY_CLASSES
		WITH SC.RDB$SECURITY_CLASS EQ secClass.c_str()
	{
		found = true;
		ERASE SC;
	}
	END_FOR

	return found;
}

void DdlNode::executeDdlTrigger(thread_db* tdbb, jrd_tra* transaction, DdlTriggerWhen when,
	int action, const MetaName& objectName, const string& sqlText)
{
	Attachment* attachment = transaction->tra_attachment;

 	// do nothing if user doesn't want database triggers
	if (attachment->att_flags & ATT_no_db_triggers)
		return;

	fb_assert(action > 0);	// first element is NULL
	DdlTriggerContext context;
	context.ddlEvent = DDL_TRIGGER_ACTION_NAMES[action];
	context.objectName = objectName;
	context.sqlText = sqlText;

	Stack<DdlTriggerContext>::AutoPushPop autoContext(attachment->ddlTriggersContext, context);
	AutoSavePoint savePoint(tdbb, transaction);

	EXE_execute_ddl_triggers(tdbb, transaction, when == DTW_BEFORE, action);

	savePoint.release();	// everything is ok
}

void DdlNode::executeDdlTrigger(thread_db* tdbb, jrd_tra* transaction,
	DdlNode::DdlTriggerWhen when, int action, const MetaName& objectName)
{
	executeDdlTrigger(tdbb, transaction, when, action, objectName, sqlText);
}

void DdlNode::putType(const TypeClause& type, bool useSubType)
{
#ifdef DEV_BUILD
	// Check if the field describes a known datatype
	if (type.type > FB_NELEM(blr_dtypes) || !blr_dtypes[type.type])
	{
		SCHAR buffer[100];

		sprintf(buffer, "Invalid dtype %d in put_dtype", type.type);
		ERRD_bugcheck(buffer);
	}
#endif

	if (type.notNull)
		dsqlScratch->appendUChar(blr_not_nullable);

	if (type.typeOfName.hasData())
	{
		if (type.typeOfTable.hasData())
		{
			if (type.collateSpecified)
			{
				dsqlScratch->appendUChar(blr_column_name2);
				dsqlScratch->appendUChar(type.fullDomain ? blr_domain_full : blr_domain_type_of);
				dsqlScratch->appendMetaString(type.typeOfTable.c_str());
				dsqlScratch->appendMetaString(type.typeOfName.c_str());
				dsqlScratch->appendUShort(type.textType);
			}
			else
			{
				dsqlScratch->appendUChar(blr_column_name);
				dsqlScratch->appendUChar(type.fullDomain ? blr_domain_full : blr_domain_type_of);
				dsqlScratch->appendMetaString(type.typeOfTable.c_str());
				dsqlScratch->appendMetaString(type.typeOfName.c_str());
			}
		}
		else
		{
			if (type.collateSpecified)
			{
				dsqlScratch->appendUChar(blr_domain_name2);
				dsqlScratch->appendUChar(type.fullDomain ? blr_domain_full : blr_domain_type_of);
				dsqlScratch->appendMetaString(type.typeOfName.c_str());
				dsqlScratch->appendUShort(type.textType);
			}
			else
			{
				dsqlScratch->appendUChar(blr_domain_name);
				dsqlScratch->appendUChar(type.fullDomain ? blr_domain_full : blr_domain_type_of);
				dsqlScratch->appendMetaString(type.typeOfName.c_str());
			}
		}

		return;
	}

	switch (type.type)
	{
		case dtype_cstring:
		case dtype_text:
		case dtype_varying:
		case dtype_blob:
			if (!useSubType)
				dsqlScratch->appendUChar(blr_dtypes[type.type]);
			else if (type.type == dtype_varying)
			{
				dsqlScratch->appendUChar(blr_varying2);
				dsqlScratch->appendUShort(type.textType);
			}
			else if (type.type == dtype_cstring)
			{
				dsqlScratch->appendUChar(blr_cstring2);
				dsqlScratch->appendUShort(type.textType);
			}
			else if (type.type == dtype_blob)
			{
				dsqlScratch->appendUChar(blr_blob2);
				dsqlScratch->appendUShort(type.subType);
				dsqlScratch->appendUShort(type.textType);
			}
			else
			{
				dsqlScratch->appendUChar(blr_text2);
				dsqlScratch->appendUShort(type.textType);
			}

			if (type.type == dtype_varying)
				dsqlScratch->appendUShort(type.length - sizeof(USHORT));
			else if (type.type != dtype_blob)
				dsqlScratch->appendUShort(type.length);
			break;

		default:
			dsqlScratch->appendUChar(blr_dtypes[type.type]);
			if (DTYPE_IS_EXACT(type.type) || dtype_quad == type.type)
				dsqlScratch->appendUChar(type.scale);
			break;
	}
}

void DdlNode::resetContextStack()
{
	dsqlScratch->context->clear();
	dsqlScratch->contextNumber = 0;
}

void DdlNode::storeGlobalField(thread_db* tdbb, jrd_tra* transaction, MetaName& name,
	const TypeClause& field, const string& computedSource, const BlrWriter::BlrData& computedValue)
{
	Attachment* attachment = transaction->tra_attachment;

	const dsql_nod* elements = field.legacyField->fld_ranges;
	const USHORT dims = elements ? elements->nod_count / 2 : 0;

	if (dims > MAX_ARRAY_DIMENSIONS)
	{
		status_exception::raise(
			Arg::Gds(isc_sqlerr) << Arg::Num(-604) <<
			Arg::Gds(isc_dsql_max_arr_dim_exceeded));
	}

	if (name.isEmpty())
		DYN_UTIL_generate_field_name(tdbb, NULL, name);

	AutoCacheRequest requestHandle(tdbb, drq_s_fld_src, DYN_REQUESTS);

	STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		FLD IN RDB$FIELDS
	{
		FLD.RDB$SYSTEM_FLAG = 0;
		strcpy(FLD.RDB$FIELD_NAME, name.c_str());

		FLD.RDB$COMPUTED_SOURCE.NULL = TRUE;
		FLD.RDB$COMPUTED_BLR.NULL = TRUE;
		FLD.RDB$DIMENSIONS.NULL = TRUE;

		updateRdbFields(field,
			FLD.RDB$FIELD_TYPE,
			FLD.RDB$FIELD_LENGTH,
			FLD.RDB$FIELD_SUB_TYPE.NULL, FLD.RDB$FIELD_SUB_TYPE,
			FLD.RDB$FIELD_SCALE.NULL, FLD.RDB$FIELD_SCALE,
			FLD.RDB$CHARACTER_SET_ID.NULL, FLD.RDB$CHARACTER_SET_ID,
			FLD.RDB$CHARACTER_LENGTH.NULL, FLD.RDB$CHARACTER_LENGTH,
			FLD.RDB$FIELD_PRECISION.NULL, FLD.RDB$FIELD_PRECISION,
			FLD.RDB$COLLATION_ID.NULL, FLD.RDB$COLLATION_ID,
			FLD.RDB$SEGMENT_LENGTH.NULL, FLD.RDB$SEGMENT_LENGTH);

		if (dims != 0)
		{
			FLD.RDB$DIMENSIONS.NULL = FALSE;
			FLD.RDB$DIMENSIONS = dims;
		}

		if (computedSource.hasData())
		{
			FLD.RDB$COMPUTED_SOURCE.NULL = FALSE;
			attachment->storeMetaDataBlob(tdbb, transaction, &FLD.RDB$COMPUTED_SOURCE,
				computedSource);
		}

		if (computedValue.hasData())
		{
			FLD.RDB$COMPUTED_BLR.NULL = FALSE;
			attachment->storeBinaryBlob(tdbb, transaction, &FLD.RDB$COMPUTED_BLR,
				computedValue);
		}
	}
	END_STORE

	if (elements)	// Is the type an array?
	{
		AutoCacheRequest request(tdbb, drq_s_fld_dym, DYN_REQUESTS);

		SSHORT position = 0;
		const dsql_nod* const* ptr = elements->nod_arg;
		for (const dsql_nod* const* const end = ptr + elements->nod_count; ptr < end; ++ptr, ++position)
		{
			const dsql_nod* element = *ptr++;
			const SLONG lrange = element->getSlong();
			element = *ptr;
			const SLONG hrange = element->getSlong();

			if (lrange >= hrange)
			{
				status_exception::raise(
					Arg::Gds(isc_sqlerr) << Arg::Num(-604) <<
					Arg::Gds(isc_dsql_arr_range_error));
			}

			STORE (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
				DIM IN RDB$FIELD_DIMENSIONS
			{
				strcpy(DIM.RDB$FIELD_NAME, name.c_str());
				DIM.RDB$DIMENSION = position;
				DIM.RDB$UPPER_BOUND = hrange;
				DIM.RDB$LOWER_BOUND = lrange;
			}
			END_STORE
		}
	}
}


//----------------------


TypeClause::TypeClause(dsql_fld* aLegacyField, const MetaName& aCollate)
	: legacyField(aLegacyField),
	  collate(aCollate)
{
}

void TypeClause::resolve(DsqlCompilerScratch* dsqlScratch, bool modifying)
{
	DDL_resolve_intl_type2(dsqlScratch, legacyField,
		(collate.isEmpty() ? NULL : MAKE_cstring(collate.c_str())), modifying);

	type = legacyField->fld_dtype;
	length = legacyField->fld_length;
	scale = legacyField->fld_scale;
	subType = legacyField->fld_sub_type;
	segLength = legacyField->fld_seg_length;
	precision = legacyField->fld_precision;
	charLength = legacyField->fld_character_length;
	charSetId = legacyField->fld_character_set_id;
	collationId = legacyField->fld_collation_id;
	collateSpecified = collate.hasData();
	textType = legacyField->fld_ttype;
	fullDomain = legacyField->fld_full_domain;
	notNull = legacyField->fld_not_nullable;
	fieldSource = legacyField->fld_source;

	if (legacyField->fld_type_of_table)
		typeOfTable = legacyField->fld_type_of_table->str_data;

	typeOfName = legacyField->fld_type_of_name;
}

void TypeClause::print(string& text) const
{
	text.printf("typeOfTable: '%s'  typeOfName: '%s'  notNull: %d  fieldSource: '%s'",
		typeOfTable.c_str(), typeOfName.c_str(), notNull, fieldSource.c_str());
}


//----------------------


ParameterClause::ParameterClause(dsql_fld* field, const MetaName& aCollate, dsql_nod* dflt,
			dsql_nod* aLegacyParameter)
	: TypeClause(field, aCollate),
	  name(field->fld_name),
	  legacyDefault(dflt),
	  legacyParameter(aLegacyParameter)
{
}

void ParameterClause::print(string& text) const
{
	string s;
	TypeClause::print(s);
	text.printf("name: '%s'  %s", name.c_str(), s.c_str());
}


//----------------------


void AlterCharSetNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"AlterCharSetNode\n"
		"  charSet: %s\n"
		"  defaultCollation: %s\n",
		charSet.c_str(), defaultCollation.c_str());
}

void AlterCharSetNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	METD_drop_charset(transaction, charSet);
	MET_dsql_cache_release(tdbb, SYM_intlsym_charset, charSet);

	bool charSetFound = false;
	bool collationFound = false;

	AutoCacheRequest requestHandle1(tdbb, drq_m_charset, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle1 TRANSACTION_HANDLE transaction)
		CS IN RDB$CHARACTER_SETS
		WITH CS.RDB$CHARACTER_SET_NAME EQ charSet.c_str()
	{
		charSetFound = true;

		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_CHARACTER_SET, charSet);

		AutoCacheRequest requestHandle2(tdbb, drq_l_collation, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle2 TRANSACTION_HANDLE transaction)
			COLL IN RDB$COLLATIONS
			WITH COLL.RDB$CHARACTER_SET_ID EQ CS.RDB$CHARACTER_SET_ID AND
				COLL.RDB$COLLATION_NAME EQ defaultCollation.c_str()
		{
			collationFound = true;
		}
		END_FOR

		if (collationFound)
		{
			MODIFY CS
				CS.RDB$DEFAULT_COLLATE_NAME.NULL = FALSE;
				strcpy(CS.RDB$DEFAULT_COLLATE_NAME, defaultCollation.c_str());
			END_MODIFY
		}
	}
	END_FOR

	if (!charSetFound)
		status_exception::raise(Arg::Gds(isc_charset_not_found) << Arg::Str(charSet));

	if (!collationFound)
	{
		status_exception::raise(
			Arg::Gds(isc_collation_not_found) << Arg::Str(defaultCollation) << Arg::Str(charSet));
	}

	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_ALTER_CHARACTER_SET, charSet);
}


//----------------------


void CommentOnNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CommentOnNode\n"
		"  objType: %s\n"
		"  objName: %s\n"
		"  text: %s\n",
		objType, objName.c_str(), text.c_str());
}

// select rdb$relation_name from rdb$relation_fields where rdb$field_name = 'RDB$DESCRIPTION';
// gives the list of objects that accept descriptions. At FB2 time, the only
// subobjects with descriptions are relation's fields and procedure's parameters.
void CommentOnNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->tra_attachment;

	const char* tableClause = NULL;
	const char* columnClause = NULL;
	const char* subColumnClause = NULL;
	const char* addWhereClause = NULL;
	Arg::StatusVector status;

	switch (objType)
	{
		case ddl_database:
			tableClause = "rdb$database";
			break;

		case ddl_domain:
			tableClause = "rdb$fields";
			columnClause = "rdb$field_name";
			status << Arg::Gds(isc_dyn_domain_not_found);
			break;

		case ddl_relation:
			if (subName.hasData())
			{
				tableClause = "rdb$relation_fields";
				subColumnClause = "rdb$field_name";
				status << Arg::Gds(isc_dyn_column_does_not_exist) <<
					Arg::Str(subName) << Arg::Str(objName);
			}
			else
			{
				tableClause = "rdb$relations";
				addWhereClause = "rdb$view_blr is null";
				status << Arg::Gds(isc_dyn_table_not_found) << Arg::Str(objName);
			}
			columnClause = "rdb$relation_name";
			break;

		case ddl_view:
			tableClause = "rdb$relations";
			columnClause = "rdb$relation_name";
			status << Arg::Gds(isc_dyn_view_not_found) << Arg::Str(objName);
			addWhereClause = "rdb$view_blr is not null";
			break;

		case ddl_procedure:
			if (subName.hasData())
			{
				tableClause = "rdb$procedure_parameters";
				subColumnClause = "rdb$parameter_name";
				status << Arg::Gds(isc_dyn_proc_param_not_found) <<
					Arg::Str(subName) << Arg::Str(objName);
			}
			else
			{
				tableClause = "rdb$procedures";
				status << Arg::Gds(isc_dyn_proc_not_found) << Arg::Str(objName);
			}

			addWhereClause = "rdb$package_name is null";
			columnClause = "rdb$procedure_name";
			break;

		case ddl_trigger:
			tableClause = "rdb$triggers";
			columnClause = "rdb$trigger_name";
			status << Arg::Gds(isc_dyn_trig_not_found) << Arg::Str(objName);
			break;

		case ddl_udf:
			tableClause = "rdb$functions";
			columnClause = "rdb$function_name";
			addWhereClause = "rdb$package_name is null";
			status << Arg::Gds(isc_dyn_func_not_found) << Arg::Str(objName);
			break;

		case ddl_blob_filter:
			tableClause = "rdb$filters";
			columnClause = "rdb$function_name";
			status << Arg::Gds(isc_dyn_filter_not_found) << Arg::Str(objName);
			break;

		case ddl_exception:
			tableClause = "rdb$exceptions";
			columnClause = "rdb$exception_name";
			status << Arg::Gds(isc_dyn_exception_not_found) << Arg::Str(objName);
			break;

		case ddl_generator:
			tableClause = "rdb$generators";
			columnClause = "rdb$generator_name";
			status << Arg::Gds(isc_dyn_gen_not_found) << Arg::Str(objName);
			break;

		case ddl_index:
			tableClause = "rdb$indices";
			columnClause = "rdb$index_name";
			status << Arg::Gds(isc_dyn_index_not_found) << Arg::Str(objName);
			break;

		case ddl_role:
			tableClause = "rdb$roles";
			columnClause = "rdb$role_name";
			status << Arg::Gds(isc_dyn_role_not_found) << Arg::Str(objName);
			break;

		case ddl_charset:
			tableClause = "rdb$character_sets";
			columnClause = "rdb$character_set_name";
			status << Arg::Gds(isc_dyn_charset_not_found) << Arg::Str(objName);
			break;

		case ddl_collation:
			tableClause = "rdb$collations";
			columnClause = "rdb$collation_name";
			status << Arg::Gds(isc_dyn_collation_not_found) << Arg::Str(objName);
			break;

		case ddl_package:
			tableClause = "rdb$packages";
			columnClause = "rdb$package_name";
			status << Arg::Gds(isc_dyn_package_not_found) << Arg::Str(objName);
			break;

		case ddl_schema:
			tableClause = "rdb$schemas";
			columnClause = "rdb$schema_name";
			status << Arg::Gds(isc_dyn_schema_not_found) << Arg::Str(objName);
			break;

		default:
			fb_assert(false);
			return;
	}

	Nullable<string> description;
	if (!text.isEmpty())
		description = attachment->stringToMetaCharSet(tdbb, text, textCharSet);

	PreparedStatement::Builder sql;
	sql << "update" << tableClause << "set rdb$description =" << description;

	if (columnClause)
	{
		sql << "where" << columnClause << "=" << objName;

		if (subColumnClause)
			sql << "and" << subColumnClause << "=" << subName;
	}

	if (addWhereClause)
		sql << "and" << addWhereClause;

	AutoPreparedStatement ps(attachment->prepareStatement(tdbb, transaction, sql));

	if (ps->executeUpdate(tdbb, transaction) == 0)
		status_exception::raise(status);
}


//----------------------


void CreateAlterFunctionNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateAlterFunctionNode\n"
		"  name: '%s'  create: %d  alter: %d\n",
		name.c_str(), create, alter);

	if (external)
	{
		string s;
		s.printf("  external -> name: '%s'  engine: '%s'\n",
			external->name.c_str(), external->engine.c_str());
		text += s;
	}

	text += "  Parameters:\n";

	for (size_t i = 0; i < parameters.getCount(); ++i)
	{
		const ParameterClause& parameter = parameters[i];

		string s;
		parameter.print(s);
		text += "    " + s + "\n";
	}
}

DdlNode* CreateAlterFunctionNode::internalDsqlPass()
{
	DsqlCompiledStatement* const statement = dsqlScratch->getStatement();
	statement->setBlockNode(this);
	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_FUNCTION);

	const dsql_nod* variables = localDeclList;
	if (variables)
	{
		// insure that variable names do not duplicate parameter names

		SortedArray<MetaName> names;

		for (size_t i = 0; i < parameters.getCount(); ++i)
		{
			ParameterClause& parameter = parameters[i];
			names.add(parameter.name);
		}

		const dsql_nod* const* ptr = variables->nod_arg;
		for (const dsql_nod* const* const end = ptr + variables->nod_count; ptr < end; ptr++)
		{
			if ((*ptr)->nod_type == nod_def_field)
			{
				const dsql_fld* field = (dsql_fld*) (*ptr)->nod_arg[e_dfl_field];
				DEV_BLKCHK(field, dsql_type_fld);

				if (names.exist(field->fld_name))
				{
					status_exception::raise(
						Arg::Gds(isc_sqlerr) << Arg::Num(-901) <<
						Arg::Gds(isc_dsql_var_conflict) <<
						Arg::Str(field->fld_name));
				}
			}
		}
	}

	source.ltrim("\n\r\t ");

	bool hasDefaultParams = false;

	// compile default expressions
	for (unsigned i = 0; i < parameters.getCount(); ++i)
	{
		ParameterClause& parameter = parameters[i];

		if (parameter.legacyDefault)
		{
			hasDefaultParams = true;
			parameter.legacyDefault->nod_arg[e_dft_default] =
				PASS1_node(dsqlScratch, parameter.legacyDefault->nod_arg[e_dft_default]);
		}
		else if (hasDefaultParams)
		{
			// parameter without default value after parameters with default
			ERRD_post(Arg::Gds(isc_sqlerr) << Arg::Num(-204) <<
					  Arg::Gds(isc_bad_default_value) <<
					  Arg::Gds(isc_invalid_clause) << Arg::Str("defaults must be last"));
		}
	}

	for (unsigned i = 0; i < parameters.getCount(); ++i)
		parameters[i].resolve(dsqlScratch);

	returnType.resolve(dsqlScratch);

	return DdlNode::internalDsqlPass();
}

void CreateAlterFunctionNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	fb_assert(create || alter);

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);
	bool altered = false;

	// first pass
	if (alter)
	{
		if (executeAlter(tdbb, transaction, false, true))
		{
			altered = true;
		}
		else
		{
			if (create)	// create or alter
				executeCreate(tdbb, transaction);
			else
				status_exception::raise(Arg::Gds(isc_dyn_func_not_found) << Arg::Str(name));
		}
	}
	else
	{
		executeCreate(tdbb, transaction);
	}

	compile(tdbb, transaction);

	executeAlter(tdbb, transaction, true, false);	// second pass

	if (package.isEmpty())
	{
		executeDdlTrigger(tdbb, transaction, DTW_AFTER,
			(altered ? DDL_TRIGGER_ALTER_FUNCTION : DDL_TRIGGER_CREATE_FUNCTION), name);
	}

	savePoint.release();	// everything is ok

	if (alter)
	{
		// Update DSQL cache
		METD_drop_function(transaction, QualifiedName(name, package));
		MET_dsql_cache_release(tdbb, SYM_udf, name, package);
	}
}

void CreateAlterFunctionNode::executeCreate(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->getAttachment();

	if (package.isEmpty())
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_FUNCTION, name);

		DYN_UTIL_check_unique_name(tdbb, transaction, name, obj_udf);
	}

	AutoCacheRequest requestHandle(tdbb, drq_s_funcs2, DYN_REQUESTS);

	int faults = 0;

	while (true)
	{
		try
		{
			SINT64 id = DYN_UTIL_gen_unique_id(tdbb, drq_g_nxt_fun_id, "RDB$FUNCTIONS");
			id %= (MAX_SSHORT + 1);

			if (!id)
				continue;

			STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
				FUN IN RDB$FUNCTIONS
			{
				FUN.RDB$FUNCTION_ID = id;
				FUN.RDB$SYSTEM_FLAG = 0;
				strcpy(FUN.RDB$FUNCTION_NAME, name.c_str());

				FUN.RDB$LEGACY_FLAG.NULL = FALSE;
				FUN.RDB$LEGACY_FLAG = 0;

				FUN.RDB$INVARIANT_FLAG.NULL = FALSE;
				FUN.RDB$INVARIANT_FLAG = invariant ? TRUE : FALSE;

				FUN.RDB$RETURN_ARGUMENT.NULL = FALSE;
				FUN.RDB$RETURN_ARGUMENT = 0;

				if (package.hasData())
				{
					FUN.RDB$PACKAGE_NAME.NULL = FALSE;
					strcpy(FUN.RDB$PACKAGE_NAME, package.c_str());

					FUN.RDB$PRIVATE_FLAG.NULL = FALSE;
					FUN.RDB$PRIVATE_FLAG = privateScope;

					FUN.RDB$OWNER_NAME.NULL = FALSE;
					strcpy(FUN.RDB$OWNER_NAME, packageOwner.c_str());
				}
				else
				{
					FUN.RDB$PACKAGE_NAME.NULL = TRUE;
					FUN.RDB$PRIVATE_FLAG.NULL = TRUE;

					FUN.RDB$OWNER_NAME.NULL = FALSE;
					strcpy(FUN.RDB$OWNER_NAME, attachment->att_user->usr_user_name.c_str());
				}
			}
			END_STORE

			break;
		}
		catch (const status_exception& ex)
		{
			if (ex.value()[1] != isc_no_dup)
				throw;

			if (++faults > MAX_SSHORT)
				throw;

			fb_utils::init_status(tdbb->tdbb_status_vector);
		}
	}

	if (package.isEmpty())
	{
		for (const TEXT* p = ALL_PROC_PRIVILEGES; *p; p++)
		{
			requestHandle.reset(tdbb, drq_s_fun_usr_prvs, DYN_REQUESTS);

			STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
				X IN RDB$USER_PRIVILEGES
			{
				strcpy(X.RDB$RELATION_NAME, name.c_str());
				strcpy(X.RDB$USER, attachment->att_user->usr_user_name.c_str());
				X.RDB$USER_TYPE = obj_user;
				X.RDB$OBJECT_TYPE = obj_udf;
				X.RDB$PRIVILEGE[0] = *p;
				X.RDB$PRIVILEGE[1] = 0;
			}
			END_STORE
		}
	}

	executeAlter(tdbb, transaction, false, false);
}

bool CreateAlterFunctionNode::executeAlter(thread_db* tdbb, jrd_tra* transaction,
	bool secondPass, bool runTriggers)
{
	Attachment* attachment = transaction->getAttachment();

	bool modified = false;

	AutoCacheRequest requestHandle(tdbb, drq_m_funcs2, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		FUN IN RDB$FUNCTIONS
		WITH FUN.RDB$FUNCTION_NAME EQ name.c_str() AND
			 FUN.RDB$PACKAGE_NAME EQUIV NULLIF(package.c_str(), '')
	{
		if (!FUN.RDB$SYSTEM_FLAG.NULL && FUN.RDB$SYSTEM_FLAG)
		{
			status_exception::raise(
				Arg::Gds(isc_dyn_cannot_mod_sysfunc) << FUN.RDB$FUNCTION_NAME);
		}

		if (!secondPass && runTriggers && package.isEmpty())
			executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_FUNCTION, name);

		MODIFY FUN
			if (secondPass)
			{
				FUN.RDB$FUNCTION_BLR.NULL = TRUE;
				FUN.RDB$DEBUG_INFO.NULL = TRUE;
			}
			else
			{
				FUN.RDB$ENGINE_NAME.NULL = TRUE;
				FUN.RDB$ENTRYPOINT.NULL = TRUE;
				FUN.RDB$FUNCTION_SOURCE.NULL = TRUE;

				FUN.RDB$VALID_BLR.NULL = FALSE;
				FUN.RDB$VALID_BLR = TRUE;

				FUN.RDB$FUNCTION_SOURCE.NULL = !(source.hasData() && (external || package.isEmpty()));
				if (!FUN.RDB$FUNCTION_SOURCE.NULL)
					attachment->storeMetaDataBlob(tdbb, transaction, &FUN.RDB$FUNCTION_SOURCE, source);
			}

			if (external)
			{
				if (!secondPass)
				{
					FUN.RDB$ENGINE_NAME.NULL = FALSE;
					strcpy(FUN.RDB$ENGINE_NAME, external->engine.c_str());

					if (external->name.length() >= sizeof(FUN.RDB$ENTRYPOINT))
					{
						status_exception::raise(
							Arg::Gds(isc_arith_except) <<
							Arg::Gds(isc_string_truncation));
					}

					FUN.RDB$ENTRYPOINT.NULL = (SSHORT) external->name.isEmpty();
					strcpy(FUN.RDB$ENTRYPOINT, external->name.c_str());
				}
			}
			else if (body)
			{
				if (secondPass)
				{
					FUN.RDB$FUNCTION_BLR.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &FUN.RDB$FUNCTION_BLR,
						dsqlScratch->getBlrData());

					FUN.RDB$DEBUG_INFO.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &FUN.RDB$DEBUG_INFO,
						dsqlScratch->getDebugData());
				}
			}

			if (package.hasData())
			{
				FUN.RDB$PRIVATE_FLAG.NULL = FALSE;
				FUN.RDB$PRIVATE_FLAG = privateScope;
			}
			else
			{
				FUN.RDB$PRIVATE_FLAG.NULL = TRUE;
			}

			modified = true;
		END_MODIFY
	}
	END_FOR

	if (!secondPass && modified)
	{
		// delete all old arguments
		DropFunctionNode::dropArguments(tdbb, transaction, name, package);

		// and insert the new ones

		ParameterClause returnParameter(returnType.legacyField, returnType.collate, NULL, NULL);
		returnParameter.resolve(dsqlScratch);
		storeArgument(tdbb, transaction, 0, returnParameter);

		for (unsigned i = 0; i < parameters.getCount(); ++i)
		{
			ParameterClause& parameter = parameters[i];
			storeArgument(tdbb, transaction, i + 1, parameter);
		}
	}

	return modified;
}

void CreateAlterFunctionNode::storeArgument(thread_db* tdbb, jrd_tra* transaction,
	unsigned pos, const ParameterClause& parameter)
{
	Attachment* attachment = transaction->getAttachment();
	DsqlCompiledStatement* statement = dsqlScratch->getStatement();

	AutoCacheRequest requestHandle(tdbb, drq_s_func_args2, DYN_REQUESTS);

	STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		ARG IN RDB$FUNCTION_ARGUMENTS
	{
		ARG.RDB$FUNCTION_NAME.NULL = FALSE;
		strcpy(ARG.RDB$FUNCTION_NAME, name.c_str());

		// Avoid the return with name INTERNAL_FIELD_NAME.
		if (parameter.name.hasData() && pos != 0)
		{
			ARG.RDB$ARGUMENT_NAME.NULL = FALSE;
			strcpy(ARG.RDB$ARGUMENT_NAME, parameter.name.c_str());
		}
		else
			ARG.RDB$ARGUMENT_NAME.NULL = TRUE;

		if (package.hasData())
		{
			ARG.RDB$PACKAGE_NAME.NULL = FALSE;
			strcpy(ARG.RDB$PACKAGE_NAME, package.c_str());
		}

		ARG.RDB$ARGUMENT_POSITION.NULL = FALSE;
		ARG.RDB$ARGUMENT_POSITION = pos;

		ARG.RDB$ARGUMENT_MECHANISM.NULL = TRUE;
		ARG.RDB$NULL_FLAG.NULL = TRUE;
		ARG.RDB$RELATION_NAME.NULL = TRUE;
		ARG.RDB$FIELD_NAME.NULL = TRUE;
		ARG.RDB$FIELD_SOURCE.NULL = TRUE;
		ARG.RDB$DEFAULT_VALUE.NULL = TRUE;
		ARG.RDB$DEFAULT_SOURCE.NULL = TRUE;

		ARG.RDB$MECHANISM.NULL = TRUE;
		ARG.RDB$FIELD_TYPE.NULL = TRUE;
		ARG.RDB$FIELD_LENGTH.NULL = TRUE;
		ARG.RDB$FIELD_PRECISION.NULL = TRUE;
		ARG.RDB$FIELD_SCALE.NULL = TRUE;
		ARG.RDB$CHARACTER_SET_ID.NULL = TRUE;
		ARG.RDB$COLLATION_ID.NULL = TRUE;

		ARG.RDB$ARGUMENT_MECHANISM.NULL = FALSE;
		ARG.RDB$ARGUMENT_MECHANISM =
			(USHORT) (parameter.fullDomain ? prm_mech_normal : prm_mech_type_of);

		if (parameter.notNull)
		{
			ARG.RDB$NULL_FLAG.NULL = FALSE;
			ARG.RDB$NULL_FLAG = TRUE;
		}

		ARG.RDB$FIELD_SOURCE.NULL = FALSE;

		if (parameter.typeOfTable.isEmpty())
		{
			if (parameter.typeOfName.hasData())
				strcpy(ARG.RDB$FIELD_SOURCE, parameter.typeOfName.c_str());
			else
			{
				MetaName fieldName;
				storeGlobalField(tdbb, transaction, fieldName, parameter);
				strcpy(ARG.RDB$FIELD_SOURCE, fieldName.c_str());
			}
		}
		else
		{
			ARG.RDB$RELATION_NAME.NULL = FALSE;
			strcpy(ARG.RDB$RELATION_NAME, parameter.typeOfTable.c_str());

			ARG.RDB$FIELD_NAME.NULL = FALSE;
			strcpy(ARG.RDB$FIELD_NAME, parameter.typeOfName.c_str());

			strcpy(ARG.RDB$FIELD_SOURCE, parameter.fieldSource.c_str());
		}

		// ASF: If we used a collate with a domain or table.column type, write it
		// into RDB$FUNCTION_ARGUMENTS.

		if (parameter.collateSpecified && parameter.typeOfName.hasData())
		{
			ARG.RDB$COLLATION_ID.NULL = FALSE;
			ARG.RDB$COLLATION_ID = parameter.collationId;
		}

		// ASF: I moved this block to write defaults on RDB$FUNCTION_ARGUMENTS.
		//		It was writing in RDB$FIELDS, but that would require special support
		//		for packaged functions signature verification.

		if (parameter.legacyDefault)
		{
			ARG.RDB$DEFAULT_VALUE.NULL = FALSE;
			ARG.RDB$DEFAULT_SOURCE.NULL = FALSE;

			dsql_str* defaultString =
				(dsql_str*) parameter.legacyDefault->nod_arg[e_dft_default_source];
			string defaultSource = string(defaultString->str_data, defaultString->str_length);
			attachment->storeMetaDataBlob(tdbb, transaction, &ARG.RDB$DEFAULT_SOURCE, defaultSource);

			dsqlScratch->getBlrData().clear();

			if (statement->getFlags() & DsqlCompiledStatement::FLAG_BLR_VERSION4)
				dsqlScratch->appendUChar(blr_version4);
			else
				dsqlScratch->appendUChar(blr_version5);

			GEN_expr(dsqlScratch, parameter.legacyDefault->nod_arg[e_dft_default]);

			dsqlScratch->appendUChar(blr_eoc);

			attachment->storeBinaryBlob(tdbb, transaction, &ARG.RDB$DEFAULT_VALUE,
				dsqlScratch->getBlrData());
		}
	}
	END_STORE
}

void CreateAlterFunctionNode::compile(thread_db* tdbb, jrd_tra* /*transaction*/)
{
	if (invalid)
		status_exception::raise(Arg::Gds(isc_dyn_invalid_ddl_func) << name);

	if (compiled)
		return;

	compiled = true;
	invalid = true;

	DsqlCompiledStatement* statement = dsqlScratch->getStatement();

	if (body)
	{
		dsqlScratch->beginDebug();
		dsqlScratch->getBlrData().clear();

		if (statement->getFlags() & DsqlCompiledStatement::FLAG_BLR_VERSION4)
			dsqlScratch->appendUChar(blr_version4);
		else
			dsqlScratch->appendUChar(blr_version5);

		dsqlScratch->appendUChar(blr_begin);

		if (parameters.getCount() != 0)
		{
			fb_assert(parameters.getCount() < size_t(MAX_USHORT / 2));
			dsqlScratch->appendUChar(blr_message);
			dsqlScratch->appendUChar(0);
			dsqlScratch->appendUShort(2 * parameters.getCount());

			for (unsigned i = 0; i < parameters.getCount(); ++i)
			{
				ParameterClause& parameter = parameters[i];
				dsqlScratch->putDebugArgument(fb_dbg_arg_input, i,
					parameter.name.c_str());
				putType(parameter, true);

				// add slot for null flag (parameter2)
				dsqlScratch->appendUChar(blr_short);
				dsqlScratch->appendUChar(0);

				variables.add(MAKE_variable(parameter.legacyField,
					parameter.name.c_str(), VAR_input, 0, (USHORT) (2 * i), 0));
			}
		}

		dsqlScratch->appendUChar(blr_message);
		dsqlScratch->appendUChar(1);
		dsqlScratch->appendUShort(2);

		dsqlScratch->putDebugArgument(fb_dbg_arg_output, 0, "");
		putType(returnType, true);

		// add slot for null flag (parameter2)
		dsqlScratch->appendUChar(blr_short);
		dsqlScratch->appendUChar(0);

		dsql_nod* const var = MAKE_variable(returnType.legacyField, "", VAR_output, 1, 0, 0);
		variables.add(var);
		outputVariables.add(var);

		if (parameters.getCount() != 0)
		{
			dsqlScratch->appendUChar(blr_receive);
			dsqlScratch->appendUChar(0);
		}

		dsqlScratch->appendUChar(blr_begin);

		for (unsigned i = 0; i < parameters.getCount(); ++i)
		{
			ParameterClause& parameter = parameters[i];

			if (parameter.fullDomain || parameter.notNull)
			{
				// ASF: To validate input parameters we need only to read its value.
				// Assigning it to null is an easy way to do this.
				dsqlScratch->appendUChar(blr_assignment);
				dsqlScratch->appendUChar(blr_parameter2);
				dsqlScratch->appendUChar(0);	// input
				dsqlScratch->appendUShort(i * 2);
				dsqlScratch->appendUShort(i * 2 + 1);
				dsqlScratch->appendUChar(blr_null);
			}
		}

		dsql_var* const variable = (dsql_var*) outputVariables[0]->nod_arg[Dsql::e_var_variable];
		putLocalVariable(dsqlScratch, variable, 0, NULL);

		// ASF: This is here to not change the old logic (proc_flag)
		// of previous calls to PASS1_node and PASS1_statement.
		dsqlScratch->setPsql(true);

		putLocalVariables(dsqlScratch, localDeclList, 1);

		dsqlScratch->appendUChar(blr_stall);
		// put a label before body of procedure,
		// so that any EXIT statement can get out
		dsqlScratch->appendUChar(blr_label);
		dsqlScratch->appendUChar(0);
		dsqlScratch->loopLevel = 0;
		dsqlScratch->cursorNumber = 0;

		GEN_statement(dsqlScratch, PASS1_statement(dsqlScratch, body));

		statement->setType(DsqlCompiledStatement::TYPE_DDL);
		dsqlScratch->appendUChar(blr_end);
		genReturn(dsqlScratch, false);

		dsqlScratch->appendUChar(blr_end);
		dsqlScratch->appendUChar(blr_eoc);

		dsqlScratch->endDebug();
	}

	invalid = false;
}


//----------------------


void DropFunctionNode::dropArguments(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& functionName, const MetaName& packageName)
{
	AutoCacheRequest requestHandle(tdbb, drq_e_func_args, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		ARG IN RDB$FUNCTION_ARGUMENTS
		WITH ARG.RDB$FUNCTION_NAME EQ functionName.c_str() AND
			 ARG.RDB$PACKAGE_NAME EQUIV NULLIF(packageName.c_str(), '')
	{
		// get rid of arguments in rdb$fields
		if (!ARG.RDB$FIELD_SOURCE.NULL)
		{
			AutoCacheRequest requestHandle2(tdbb, drq_e_arg_gfld, DYN_REQUESTS);

			FOR (REQUEST_HANDLE requestHandle2 TRANSACTION_HANDLE transaction)
				FLD IN RDB$FIELDS
				WITH FLD.RDB$FIELD_NAME EQ ARG.RDB$FIELD_SOURCE AND
					 FLD.RDB$FIELD_NAME STARTING WITH IMPLICIT_DOMAIN_PREFIX
			{
				bool erase = true;

				AutoCacheRequest requestHandle3(tdbb, drq_e_arg_gfld2, DYN_REQUESTS);

				FOR (REQUEST_HANDLE requestHandle3 TRANSACTION_HANDLE transaction)
					ARG2 IN RDB$FUNCTION_ARGUMENTS
					WITH ARG2.RDB$FUNCTION_NAME = ARG.RDB$FUNCTION_NAME AND
						 ARG2.RDB$PACKAGE_NAME EQUIV
					 		NULLIF(packageName.c_str(), '') AND
						 ARG2.RDB$ARGUMENT_NAME = ARG.RDB$ARGUMENT_NAME
				{
					if (!ARG2.RDB$RELATION_NAME.NULL && !ARG2.RDB$FIELD_NAME.NULL)
						erase = false;
				}
				END_FOR

				if (erase)
					ERASE FLD;
			}
			END_FOR
		}

		ERASE ARG;
	}
	END_FOR
}

void DropFunctionNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropFunctionNode\n"
		"  name: '%s'\n",
		name.c_str());
}

DdlNode* DropFunctionNode::internalDsqlPass()
{
	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_FUNCTION);
	return DdlNode::internalDsqlPass();
}

void DropFunctionNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);
	bool found = false;

	dropArguments(tdbb, transaction, name, package);

	AutoCacheRequest requestHandle(tdbb, drq_e_funcs, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		FUN IN RDB$FUNCTIONS
		WITH FUN.RDB$FUNCTION_NAME EQ name.c_str() AND
			 FUN.RDB$PACKAGE_NAME EQUIV NULLIF(package.c_str(), '')
	{
		if (!FUN.RDB$SYSTEM_FLAG.NULL && FUN.RDB$SYSTEM_FLAG)
			status_exception::raise(Arg::Gds(isc_dyn_cannot_mod_sysfunc) << FUN.RDB$FUNCTION_NAME);

		if (package.isEmpty())
			executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_DROP_FUNCTION, name);

		ERASE FUN;

		if (!FUN.RDB$SECURITY_CLASS.NULL)
			deleteSecurityClass(tdbb, transaction, FUN.RDB$SECURITY_CLASS);

		found = true;
	}
	END_FOR

	if (!found && !silent)
		status_exception::raise(Arg::Gds(isc_dyn_func_not_found) << Arg::Str(name));

	if (package.isEmpty())
	{
		requestHandle.reset(tdbb, drq_e_fun_prvs, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
			PRIV IN RDB$USER_PRIVILEGES WITH PRIV.RDB$RELATION_NAME EQ name.c_str()
				AND PRIV.RDB$OBJECT_TYPE = obj_udf
		{
			ERASE PRIV;
		}
		END_FOR

		requestHandle.reset(tdbb, drq_e_fun_prv, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
			PRIV IN RDB$USER_PRIVILEGES WITH PRIV.RDB$USER EQ name.c_str()
				AND PRIV.RDB$USER_TYPE = obj_udf
		{
			ERASE PRIV;
		}
		END_FOR
	}

	if (found && package.isEmpty())
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_DROP_FUNCTION, name);

	savePoint.release();	// everything is ok

	// Update DSQL cache
	METD_drop_function(transaction, QualifiedName(name, package));
	MET_dsql_cache_release(tdbb, SYM_udf, name, package);
}


//----------------------


void RecreateFunctionNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf("RecreateFunctionNode\n");
}

DdlNode* RecreateFunctionNode::internalDsqlPass()
{
	createNode->dsqlPass(dsqlScratch);
	dropNode.dsqlPass(dsqlScratch);
	return DdlNode::internalDsqlPass();
}

void RecreateFunctionNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	dropNode.execute(tdbb, transaction);
	createNode->execute(tdbb, transaction);

	savePoint.release();	// everything is ok
}


//----------------------


void CreateAlterProcedureNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateAlterProcedureNode\n"
		"  name: '%s'  create: %d  alter: %d\n",
		name.c_str(), create, alter);

	if (external)
	{
		string s;
		s.printf("  external -> name: '%s'  engine: '%s'\n",
			external->name.c_str(), external->engine.c_str());
		text += s;
	}

	text += "  Parameters:\n";

	for (size_t i = 0; i < parameters.getCount(); ++i)
	{
		const ParameterClause& parameter = parameters[i];

		string s;
		parameter.print(s);
		text += "    " + s + "\n";
	}

	text += "  Returns:\n";

	for (size_t i = 0; i < returns.getCount(); ++i)
	{
		const ParameterClause& parameter = returns[i];

		string s;
		parameter.print(s);
		text += "    " + s + "\n";
	}
}

DdlNode* CreateAlterProcedureNode::internalDsqlPass()
{
	DsqlCompiledStatement* statement = dsqlScratch->getStatement();
	statement->setBlockNode(this);
	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_PROCEDURE);

	const dsql_nod* variables = localDeclList;
	if (variables)
	{
		// insure that variable names do not duplicate parameter names

		SortedArray<MetaName> names;

		for (size_t i = 0; i < parameters.getCount(); ++i)
		{
			ParameterClause& parameter = parameters[i];
			names.add(parameter.name);
		}

		for (size_t i = 0; i < returns.getCount(); ++i)
		{
			ParameterClause& parameter = returns[i];
			names.add(parameter.name);
		}

		const dsql_nod* const* ptr = variables->nod_arg;
		for (const dsql_nod* const* const end = ptr + variables->nod_count; ptr < end; ptr++)
		{
			if ((*ptr)->nod_type == nod_def_field)
			{
				const dsql_fld* field = (dsql_fld*) (*ptr)->nod_arg[e_dfl_field];
				DEV_BLKCHK(field, dsql_type_fld);

				if (names.exist(field->fld_name))
				{
					status_exception::raise(
						Arg::Gds(isc_sqlerr) << Arg::Num(-901) <<
						Arg::Gds(isc_dsql_var_conflict) << Arg::Str(field->fld_name));
				}
			}
		}
	}

	source.ltrim("\n\r\t ");

	bool hasDefaultParams = false;

	// compile default expressions
	for (unsigned i = 0; i < parameters.getCount(); ++i)
	{
		ParameterClause& parameter = parameters[i];

		if (parameter.legacyDefault)
		{
			hasDefaultParams = true;
			parameter.legacyDefault->nod_arg[e_dft_default] =
				PASS1_node(dsqlScratch, parameter.legacyDefault->nod_arg[e_dft_default]);
		}
		else if (hasDefaultParams)
		{
			// parameter without default value after parameters with default
			ERRD_post(Arg::Gds(isc_sqlerr) << Arg::Num(-204) <<
					  Arg::Gds(isc_bad_default_value) <<
					  Arg::Gds(isc_invalid_clause) << Arg::Str("defaults must be last"));
		}
	}

	for (unsigned i = 0; i < parameters.getCount(); ++i)
		parameters[i].resolve(dsqlScratch);

	for (unsigned i = 0; i < returns.getCount(); ++i)
		returns[i].resolve(dsqlScratch);

	return DdlNode::internalDsqlPass();
}

void CreateAlterProcedureNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	fb_assert(create || alter);

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);
	bool altered = false;

	// first pass
	if (alter)
	{
		if (executeAlter(tdbb, transaction, false, true))
			altered = true;
		else
		{
			if (create)	// create or alter
				executeCreate(tdbb, transaction);
			else
				status_exception::raise(Arg::Gds(isc_dyn_proc_not_found) << Arg::Str(name));
		}
	}
	else
		executeCreate(tdbb, transaction);

	compile(tdbb, transaction);

	executeAlter(tdbb, transaction, true, false);	// second pass

	if (package.isEmpty())
	{
		executeDdlTrigger(tdbb, transaction, DTW_AFTER,
			(altered ? DDL_TRIGGER_ALTER_PROCEDURE : DDL_TRIGGER_CREATE_PROCEDURE), name);
	}

	savePoint.release();	// everything is ok

	if (alter)
	{
		// Update DSQL cache
		METD_drop_procedure(transaction, QualifiedName(name, package));
		MET_dsql_cache_release(tdbb, SYM_procedure, name, package);
	}
}

void CreateAlterProcedureNode::executeCreate(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->getAttachment();

	if (package.isEmpty())
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_PROCEDURE, name);

		DYN_UTIL_check_unique_name(tdbb, transaction, name, obj_procedure);
	}

	AutoCacheRequest requestHandle(tdbb, drq_s_prcs2, DYN_REQUESTS);

	int faults = 0;

	while (true)
	{
		try
		{
			SINT64 id = DYN_UTIL_gen_unique_id(tdbb, drq_g_nxt_prc_id, "RDB$PROCEDURES");
			id %= (MAX_SSHORT + 1);

			if (!id)
				continue;

			STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
				P IN RDB$PROCEDURES
			{
				P.RDB$PROCEDURE_ID = id;
				P.RDB$SYSTEM_FLAG = 0;
				strcpy(P.RDB$PROCEDURE_NAME, name.c_str());

				if (package.hasData())
				{
					P.RDB$PACKAGE_NAME.NULL = FALSE;
					strcpy(P.RDB$PACKAGE_NAME, package.c_str());

					P.RDB$PRIVATE_FLAG.NULL = FALSE;
					P.RDB$PRIVATE_FLAG = privateScope;

					strcpy(P.RDB$OWNER_NAME, packageOwner.c_str());
				}
				else
				{
					P.RDB$PACKAGE_NAME.NULL = TRUE;
					P.RDB$PRIVATE_FLAG.NULL = TRUE;

					strcpy(P.RDB$OWNER_NAME, attachment->att_user->usr_user_name.c_str());
				}
			}
			END_STORE

			break;
		}
		catch (const status_exception& ex)
		{
			if (ex.value()[1] != isc_no_dup)
				throw;

			if (++faults > MAX_SSHORT)
				throw;

			fb_utils::init_status(tdbb->tdbb_status_vector);
		}
	}

	if (package.isEmpty())
	{
		for (const TEXT* p = ALL_PROC_PRIVILEGES; *p; p++)
		{
			requestHandle.reset(tdbb, drq_s_prc_usr_prvs, DYN_REQUESTS);

			STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
				X IN RDB$USER_PRIVILEGES
			{
				strcpy(X.RDB$RELATION_NAME, name.c_str());
				strcpy(X.RDB$USER, attachment->att_user->usr_user_name.c_str());
				X.RDB$USER_TYPE = obj_user;
				X.RDB$OBJECT_TYPE = obj_procedure;
				X.RDB$PRIVILEGE[0] = *p;
				X.RDB$PRIVILEGE[1] = 0;
			}
			END_STORE
		}
	}

	executeAlter(tdbb, transaction, false, false);
}

bool CreateAlterProcedureNode::executeAlter(thread_db* tdbb, jrd_tra* transaction,
	bool secondPass, bool runTriggers)
{
	Attachment* attachment = transaction->getAttachment();
	AutoCacheRequest requestHandle(tdbb, drq_m_prcs2, DYN_REQUESTS);
	bool modified = false;

	DsqlCompiledStatement* statement = dsqlScratch->getStatement();

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		P IN RDB$PROCEDURES
		WITH P.RDB$PROCEDURE_NAME EQ name.c_str() AND
			 P.RDB$PACKAGE_NAME EQUIV NULLIF(package.c_str(), '')
	{
		if (!P.RDB$SYSTEM_FLAG.NULL && P.RDB$SYSTEM_FLAG)
		{
			status_exception::raise(Arg::Gds(isc_dyn_cannot_mod_sysproc) << P.RDB$PROCEDURE_NAME);
		}

		if (!secondPass && runTriggers && package.isEmpty())
			executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_PROCEDURE, name);

		MODIFY P
			if (secondPass)
			{
				P.RDB$PROCEDURE_BLR.NULL = TRUE;
				P.RDB$DEBUG_INFO.NULL = TRUE;
				P.RDB$PROCEDURE_TYPE.NULL = TRUE;

				P.RDB$PROCEDURE_INPUTS = (USHORT) parameters.getCount();
				P.RDB$PROCEDURE_OUTPUTS = (USHORT) returns.getCount();
			}
			else
			{
				P.RDB$ENGINE_NAME.NULL = TRUE;
				P.RDB$ENTRYPOINT.NULL = TRUE;
				P.RDB$PROCEDURE_SOURCE.NULL = TRUE;

				P.RDB$VALID_BLR = TRUE;

				P.RDB$PROCEDURE_SOURCE.NULL = !(source.hasData() && (external || package.isEmpty()));
				if (!P.RDB$PROCEDURE_SOURCE.NULL)
					attachment->storeMetaDataBlob(tdbb, transaction, &P.RDB$PROCEDURE_SOURCE, source);

				if (package.hasData())
				{
					P.RDB$PRIVATE_FLAG.NULL = FALSE;
					P.RDB$PRIVATE_FLAG = privateScope;
				}
				else
					P.RDB$PRIVATE_FLAG.NULL = TRUE;
			}

			if (external)
			{
				if (secondPass)
				{
					P.RDB$PROCEDURE_TYPE.NULL = FALSE;
					P.RDB$PROCEDURE_TYPE = (USHORT) prc_selectable;
				}
				else
				{
					P.RDB$ENGINE_NAME.NULL = FALSE;
					strcpy(P.RDB$ENGINE_NAME, external->engine.c_str());

					if (external->name.length() >= sizeof(P.RDB$ENTRYPOINT))
					{
						status_exception::raise(
							Arg::Gds(isc_arith_except) <<
							Arg::Gds(isc_string_truncation));
					}

					P.RDB$ENTRYPOINT.NULL = (SSHORT) external->name.isEmpty();
					strcpy(P.RDB$ENTRYPOINT, external->name.c_str());
				}
			}
			else if (body)
			{
				if (secondPass)
				{
					P.RDB$PROCEDURE_BLR.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &P.RDB$PROCEDURE_BLR,
						dsqlScratch->getBlrData());

					P.RDB$DEBUG_INFO.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &P.RDB$DEBUG_INFO,
						dsqlScratch->getDebugData());

					P.RDB$PROCEDURE_TYPE.NULL = FALSE;
					P.RDB$PROCEDURE_TYPE = (USHORT)
						(statement->getFlags() & DsqlCompiledStatement::FLAG_SELECTABLE ?
							prc_selectable : prc_executable);
				}
			}

			modified = true;
		END_MODIFY
	}
	END_FOR

	if (!secondPass && modified)
	{
		// delete all old input and output parameters
		DropProcedureNode::dropParameters(tdbb, transaction, name, package);

		// and insert the new ones

		for (unsigned i = 0; i < parameters.getCount(); ++i)
		{
			ParameterClause& parameter = parameters[i];
			storeParameter(tdbb, transaction, 0, i, parameter);
		}

		for (unsigned i = 0; i < returns.getCount(); ++i)
		{
			ParameterClause& parameter = returns[i];
			storeParameter(tdbb, transaction, 1, i, parameter);
		}

		AutoCacheRequest requestHandle2(tdbb, drq_m_prm_view, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle2 TRANSACTION_HANDLE transaction)
			PRM IN RDB$PROCEDURE_PARAMETERS CROSS
			RFR IN RDB$RELATION_FIELDS CROSS
			VRL IN RDB$VIEW_RELATIONS
			WITH PRM.RDB$PROCEDURE_NAME EQ name.c_str() AND
				 PRM.RDB$PACKAGE_NAME EQUIV NULLIF(package.c_str(), '') AND
				 VRL.RDB$RELATION_NAME EQ PRM.RDB$PROCEDURE_NAME AND
				 VRL.RDB$PACKAGE_NAME EQUIV PRM.RDB$PACKAGE_NAME AND
				 VRL.RDB$CONTEXT_TYPE EQ VCT_PROCEDURE AND
				 RFR.RDB$RELATION_NAME EQ VRL.RDB$VIEW_NAME AND
				 RFR.RDB$VIEW_CONTEXT EQ VRL.RDB$VIEW_CONTEXT AND
				 RFR.RDB$BASE_FIELD = PRM.RDB$PARAMETER_NAME
		{
			MODIFY RFR
			{
				strcpy(RFR.RDB$FIELD_SOURCE, PRM.RDB$FIELD_SOURCE);
			}
			END_MODIFY
		}
		END_FOR
	}

	return modified;
}

void CreateAlterProcedureNode::storeParameter(thread_db* tdbb, jrd_tra* transaction,
	USHORT type, unsigned pos, const ParameterClause& parameter)
{
	Attachment* attachment = transaction->getAttachment();

	AutoCacheRequest requestHandle(tdbb, drq_s_prms4, DYN_REQUESTS);

	STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		PRM IN RDB$PROCEDURE_PARAMETERS
	{
		PRM.RDB$PARAMETER_NAME.NULL = FALSE;
		strcpy(PRM.RDB$PARAMETER_NAME, parameter.name.c_str());

		PRM.RDB$PROCEDURE_NAME.NULL = FALSE;
		strcpy(PRM.RDB$PROCEDURE_NAME, name.c_str());

		if (package.hasData())
		{
			PRM.RDB$PACKAGE_NAME.NULL = FALSE;
			strcpy(PRM.RDB$PACKAGE_NAME, package.c_str());
		}
		else
			PRM.RDB$PACKAGE_NAME.NULL = TRUE;

		PRM.RDB$SYSTEM_FLAG = 0;
		PRM.RDB$SYSTEM_FLAG.NULL = FALSE;

		PRM.RDB$PARAMETER_NUMBER.NULL = FALSE;
		PRM.RDB$PARAMETER_NUMBER = pos;

		PRM.RDB$PARAMETER_TYPE.NULL = FALSE;
		PRM.RDB$PARAMETER_TYPE = type;

		PRM.RDB$PARAMETER_MECHANISM.NULL = FALSE;
		PRM.RDB$PARAMETER_MECHANISM =
			(USHORT) (parameter.fullDomain ? prm_mech_normal : prm_mech_type_of);

		PRM.RDB$NULL_FLAG.NULL = !parameter.notNull;
		PRM.RDB$NULL_FLAG = parameter.notNull;

		PRM.RDB$RELATION_NAME.NULL = parameter.typeOfTable.isEmpty();
		PRM.RDB$FIELD_NAME.NULL = PRM.RDB$RELATION_NAME.NULL || parameter.typeOfName.isEmpty();

		PRM.RDB$FIELD_SOURCE.NULL = FALSE;

		if (PRM.RDB$RELATION_NAME.NULL)
		{
			if (parameter.typeOfName.hasData())
				strcpy(PRM.RDB$FIELD_SOURCE, parameter.typeOfName.c_str());
			else
			{
				MetaName fieldName;
				storeGlobalField(tdbb, transaction, fieldName, parameter);
				strcpy(PRM.RDB$FIELD_SOURCE, fieldName.c_str());
			}
		}
		else
		{
			strcpy(PRM.RDB$RELATION_NAME, parameter.typeOfTable.c_str());
			strcpy(PRM.RDB$FIELD_NAME, parameter.typeOfName.c_str());
			strcpy(PRM.RDB$FIELD_SOURCE, parameter.fieldSource.c_str());
		}

		// ASF: If we used a collate with a domain or table.column type, write it
		// in RDB$PROCEDURE_PARAMETERS.

		PRM.RDB$COLLATION_ID.NULL = !(parameter.collateSpecified && parameter.typeOfName.hasData());

		if (!PRM.RDB$COLLATION_ID.NULL)
			PRM.RDB$COLLATION_ID = parameter.collationId;

		// ASF: I moved this block to write defaults on RDB$PROCEDURE_PARAMETERS.
		// It was writing in RDB$FIELDS, but that would require special support
		// for packaged procedures signature verification.

		PRM.RDB$DEFAULT_VALUE.NULL = !parameter.legacyDefault;
		PRM.RDB$DEFAULT_SOURCE.NULL = !parameter.legacyDefault;

		if (parameter.legacyDefault)
		{
			dsql_str* defaultString =
				(dsql_str*) parameter.legacyDefault->nod_arg[e_dft_default_source];
			string defaultSource = string(defaultString->str_data, defaultString->str_length);
			attachment->storeMetaDataBlob(tdbb, transaction, &PRM.RDB$DEFAULT_SOURCE, defaultSource);

			DsqlCompiledStatement* statement = dsqlScratch->getStatement();

			dsqlScratch->getBlrData().clear();

			if (statement->getFlags() & DsqlCompiledStatement::FLAG_BLR_VERSION4)
				dsqlScratch->appendUChar(blr_version4);
			else
				dsqlScratch->appendUChar(blr_version5);

			GEN_expr(dsqlScratch, parameter.legacyDefault->nod_arg[e_dft_default]);

			dsqlScratch->appendUChar(blr_eoc);

			attachment->storeBinaryBlob(tdbb, transaction, &PRM.RDB$DEFAULT_VALUE,
				dsqlScratch->getBlrData());
		}
	}
	END_STORE
}

void CreateAlterProcedureNode::compile(thread_db* tdbb, jrd_tra* /*transaction*/)
{
	if (invalid)
		status_exception::raise(Arg::Gds(isc_dyn_invalid_ddl_proc) << name);

	if (compiled)
		return;

	compiled = true;

	if (!body)
		return;

	invalid = true;

	DsqlCompiledStatement* statement = dsqlScratch->getStatement();

	dsqlScratch->beginDebug();
	dsqlScratch->getBlrData().clear();

	if (statement->getFlags() & DsqlCompiledStatement::FLAG_BLR_VERSION4)
		dsqlScratch->appendUChar(blr_version4);
	else
		dsqlScratch->appendUChar(blr_version5);

	dsqlScratch->appendUChar(blr_begin);

	if (parameters.getCount() != 0)
	{
		fb_assert(parameters.getCount() < MAX_USHORT / 2);
		dsqlScratch->appendUChar(blr_message);
		dsqlScratch->appendUChar(0);
		dsqlScratch->appendUShort(2 * parameters.getCount());

		for (unsigned i = 0; i < parameters.getCount(); ++i)
		{
			ParameterClause& parameter = parameters[i];
			dsqlScratch->putDebugArgument(fb_dbg_arg_input, i, parameter.name.c_str());
			putType(parameter, true);

			// add slot for null flag (parameter2)
			dsqlScratch->appendUChar(blr_short);
			dsqlScratch->appendUChar(0);

			variables.add(MAKE_variable(parameter.legacyField,
				parameter.name.c_str(), VAR_input, 0, (USHORT) (2 * i), 0));
		}
	}

	fb_assert(returns.getCount() < MAX_USHORT / 2);
	dsqlScratch->appendUChar(blr_message);
	dsqlScratch->appendUChar(1);
	dsqlScratch->appendUShort(2 * returns.getCount() + 1);

	if (returns.getCount() != 0)
	{
		for (unsigned i = 0; i < returns.getCount(); ++i)
		{
			ParameterClause& parameter = returns[i];
			dsqlScratch->putDebugArgument(fb_dbg_arg_output, i, parameter.name.c_str());
			putType(parameter, true);

			// add slot for null flag (parameter2)
			dsqlScratch->appendUChar(blr_short);
			dsqlScratch->appendUChar(0);

			dsql_nod* const var = MAKE_variable(parameter.legacyField,
				parameter.name.c_str(), VAR_output, 1, (USHORT) (2 * i), i);

			variables.add(var);
			outputVariables.add(var);
		}
	}

	// add slot for EOS
	dsqlScratch->appendUChar(blr_short);
	dsqlScratch->appendUChar(0);

	if (parameters.getCount() != 0)
	{
		dsqlScratch->appendUChar(blr_receive);
		dsqlScratch->appendUChar(0);
	}

	dsqlScratch->appendUChar(blr_begin);

	for (unsigned i = 0; i < parameters.getCount(); ++i)
	{
		ParameterClause& parameter = parameters[i];

		if (parameter.fullDomain || parameter.notNull)
		{
			// ASF: To validate an input parameter we need only to read its value.
			// Assigning it to null is an easy way to do this.
			dsqlScratch->appendUChar(blr_assignment);
			dsqlScratch->appendUChar(blr_parameter2);
			dsqlScratch->appendUChar(0);	// input
			dsqlScratch->appendUShort(i * 2);
			dsqlScratch->appendUShort(i * 2 + 1);
			dsqlScratch->appendUChar(blr_null);
		}
	}

	for (Array<dsql_nod*>::const_iterator i = outputVariables.begin(); i != outputVariables.end(); ++i)
	{
		dsql_nod* parameter = *i;
		dsql_var* const variable = (dsql_var*) parameter->nod_arg[Dsql::e_var_variable];
		putLocalVariable(dsqlScratch, variable, 0, NULL);
	}

	// ASF: This is here to not change the old logic (proc_flag)
	// of previous calls to PASS1_node and PASS1_statement.
	dsqlScratch->setPsql(true);

	putLocalVariables(dsqlScratch, localDeclList, returns.getCount());

	dsqlScratch->appendUChar(blr_stall);
	// put a label before body of procedure,
	// so that any EXIT statement can get out
	dsqlScratch->appendUChar(blr_label);
	dsqlScratch->appendUChar(0);
	dsqlScratch->loopLevel = 0;
	dsqlScratch->cursorNumber = 0;

	GEN_statement(dsqlScratch, PASS1_statement(dsqlScratch, body));

	statement->setType(DsqlCompiledStatement::TYPE_DDL);
	dsqlScratch->appendUChar(blr_end);
	genReturn(dsqlScratch, true);

	dsqlScratch->appendUChar(blr_end);
	dsqlScratch->appendUChar(blr_eoc);

	dsqlScratch->endDebug();

	invalid = false;
}


//----------------------


void DropProcedureNode::dropParameters(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& procedureName, const MetaName& packageName)
{
	AutoCacheRequest requestHandle(tdbb, drq_e_prms2, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		PRM IN RDB$PROCEDURE_PARAMETERS
		WITH PRM.RDB$PROCEDURE_NAME EQ procedureName.c_str() AND
			 PRM.RDB$PACKAGE_NAME EQUIV NULLIF(packageName.c_str(), '')
	{
		// get rid of parameters in rdb$fields
		if (!PRM.RDB$FIELD_SOURCE.NULL && PRM.RDB$RELATION_NAME.NULL && PRM.RDB$FIELD_NAME.NULL)
		{
			AutoCacheRequest requestHandle2(tdbb, drq_e_prm_gfld, DYN_REQUESTS);

			FOR (REQUEST_HANDLE requestHandle2 TRANSACTION_HANDLE transaction)
				FLD IN RDB$FIELDS
				WITH FLD.RDB$FIELD_NAME EQ PRM.RDB$FIELD_SOURCE AND
					 FLD.RDB$FIELD_NAME STARTING WITH IMPLICIT_DOMAIN_PREFIX AND
					 (FLD.RDB$SYSTEM_FLAG EQ 0 OR FLD.RDB$SYSTEM_FLAG MISSING)
			{
				ERASE FLD;
			}
			END_FOR
		}

		ERASE PRM;
	}
	END_FOR
}

void DropProcedureNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropProcedureNode\n"
		"  name: '%s'\n",
		name.c_str());
}

DdlNode* DropProcedureNode::internalDsqlPass()
{
	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_PROCEDURE);
	return DdlNode::internalDsqlPass();
}

void DropProcedureNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);
	bool found = false;

	dropParameters(tdbb, transaction, name, package);

	AutoCacheRequest requestHandle(tdbb, drq_e_prcs2, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		PRC IN RDB$PROCEDURES
		WITH PRC.RDB$PROCEDURE_NAME EQ name.c_str() AND
			 PRC.RDB$PACKAGE_NAME EQUIV NULLIF(package.c_str(), '')
	{
		if (!PRC.RDB$SYSTEM_FLAG.NULL && PRC.RDB$SYSTEM_FLAG)
			status_exception::raise(Arg::Gds(isc_dyn_cannot_mod_sysproc) << PRC.RDB$PROCEDURE_NAME);

		if (package.isEmpty())
			executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_DROP_PROCEDURE, name);

		ERASE PRC;

		if (!PRC.RDB$SECURITY_CLASS.NULL)
			deleteSecurityClass(tdbb, transaction, PRC.RDB$SECURITY_CLASS);

		found = true;
	}
	END_FOR

	if (!found && !silent)
		status_exception::raise(Arg::Gds(isc_dyn_proc_not_found) << Arg::Str(name));

	if (package.isEmpty())
	{
		requestHandle.reset(tdbb, drq_e_prc_prvs, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
			PRIV IN RDB$USER_PRIVILEGES WITH PRIV.RDB$RELATION_NAME EQ name.c_str()
				AND PRIV.RDB$OBJECT_TYPE = obj_procedure
		{
			ERASE PRIV;
		}
		END_FOR

		requestHandle.reset(tdbb, drq_e_prc_prv, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
			PRIV IN RDB$USER_PRIVILEGES WITH PRIV.RDB$USER EQ name.c_str()
				AND PRIV.RDB$USER_TYPE = obj_procedure
		{
			ERASE PRIV;
		}
		END_FOR
	}

	if (found && package.isEmpty())
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_DROP_PROCEDURE, name);

	savePoint.release();	// everything is ok

	// Update DSQL cache
	METD_drop_procedure(transaction, QualifiedName(name, package));
	MET_dsql_cache_release(tdbb, SYM_procedure, name, package);
}


//----------------------


void RecreateProcedureNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf("RecreateProcedureNode\n");
}

DdlNode* RecreateProcedureNode::internalDsqlPass()
{
	dropNode.dsqlPass(dsqlScratch);
	createNode->dsqlPass(dsqlScratch);
	return DdlNode::internalDsqlPass();
}

void RecreateProcedureNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	dropNode.execute(tdbb, transaction);
	createNode->execute(tdbb, transaction);

	savePoint.release();	// everything is ok
}


//----------------------


void TriggerDefinition::store(thread_db* tdbb, jrd_tra* transaction)
{
	if (name.isEmpty())
		DYN_UTIL_generate_trigger_name(tdbb, transaction, name);

	AutoCacheRequest requestHandle(tdbb, drq_s_triggers2, DYN_REQUESTS);

	STORE (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		TRG IN RDB$TRIGGERS
	{
		TRG.RDB$SYSTEM_FLAG = SSHORT(systemFlag);
		TRG.RDB$FLAGS = TRG_sql | (fkTrigger ? TRG_ignore_perm : 0);
		strcpy(TRG.RDB$TRIGGER_NAME, name.c_str());

		TRG.RDB$RELATION_NAME.NULL = relationName.isEmpty();
		strcpy(TRG.RDB$RELATION_NAME, relationName.c_str());

		fb_assert(type.specified);
		TRG.RDB$TRIGGER_TYPE = type.value;

		TRG.RDB$TRIGGER_SEQUENCE = (!position.specified ? 0 : position.value);
		TRG.RDB$TRIGGER_INACTIVE = (!active.specified ? 0 : (USHORT) !active.value);
	}
	END_STORE

	modify(tdbb, transaction);
}

bool TriggerDefinition::modify(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->getAttachment();
	bool modified = false;

	// ASF: Unregistered bug (2.0, 2.1, 2.5, 3.0): CREATE OR ALTER TRIGGER accepts different table
	// than one used in already created trigger.

	AutoCacheRequest requestHandle(tdbb, drq_m_trigger2, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		TRG IN RDB$TRIGGERS
		WITH TRG.RDB$TRIGGER_NAME EQ name.c_str()
	{
		if (type.specified && type.value != (FB_UINT64) TRG.RDB$TRIGGER_TYPE &&
			TRG.RDB$RELATION_NAME.NULL)
		{
			status_exception::raise(
				Arg::Gds(isc_dsql_command_err) <<
				Arg::Gds(isc_dsql_db_trigger_type_cant_change));
		}

		if (systemFlag == fb_sysflag_user && !TRG.RDB$SYSTEM_FLAG.NULL)
		{
			switch (TRG.RDB$SYSTEM_FLAG)
			{
				case fb_sysflag_check_constraint:
				case fb_sysflag_referential_constraint:
				case fb_sysflag_view_check:
					status_exception::raise(Arg::Gds(isc_dyn_cant_modify_auto_trig));
					break;

				case fb_sysflag_system:
					status_exception::raise(
						Arg::Gds(isc_dyn_cannot_mod_systrig) << TRG.RDB$TRIGGER_NAME);
					break;

				default:
					break;
			}
		}

		preModify(tdbb, transaction);

		MODIFY TRG
			if (blrData.length > 0 || external)
			{
				fb_assert(!(blrData.length > 0 && external));

				TRG.RDB$ENGINE_NAME.NULL = TRUE;
				TRG.RDB$ENTRYPOINT.NULL = TRUE;
				TRG.RDB$TRIGGER_SOURCE.NULL = TRUE;
				TRG.RDB$TRIGGER_BLR.NULL = TRUE;
				TRG.RDB$DEBUG_INFO.NULL = TRUE;
			}

			if (type.specified)
				TRG.RDB$TRIGGER_TYPE = type.value;

			if (position.specified)
				TRG.RDB$TRIGGER_SEQUENCE = position.value;
			if (active.specified)
				TRG.RDB$TRIGGER_INACTIVE = (USHORT) !active.value;

			if (external)
			{
				TRG.RDB$ENGINE_NAME.NULL = FALSE;
				strcpy(TRG.RDB$ENGINE_NAME, external->engine.c_str());

				if (external->name.length() >= sizeof(TRG.RDB$ENTRYPOINT))
				{
					status_exception::raise(
						Arg::Gds(isc_arith_except) <<
						Arg::Gds(isc_string_truncation));
				}

				TRG.RDB$ENTRYPOINT.NULL = (SSHORT) external->name.isEmpty();
				strcpy(TRG.RDB$ENTRYPOINT, external->name.c_str());
			}
			else if (blrData.length > 0)
			{
				TRG.RDB$TRIGGER_BLR.NULL = FALSE;
				attachment->storeBinaryBlob(tdbb, transaction, &TRG.RDB$TRIGGER_BLR, blrData);
			}

			if (debugData.length > 0)
			{
				TRG.RDB$DEBUG_INFO.NULL = FALSE;
				attachment->storeBinaryBlob(tdbb, transaction, &TRG.RDB$DEBUG_INFO, debugData);
			}

			if (source.hasData())
			{
				TRG.RDB$TRIGGER_SOURCE.NULL = FALSE;
				attachment->storeMetaDataBlob(tdbb, transaction, &TRG.RDB$TRIGGER_SOURCE, source);
			}

			TRG.RDB$VALID_BLR = TRUE;

			modified = true;
		END_MODIFY
	}
	END_FOR

	if (modified)
		postModify(tdbb, transaction);

	return modified;
}


//----------------------


void CreateAlterTriggerNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateAlterTriggerNode\n"
		"  name: '%s'  create: %d  alter: %d  relationName: '%s'\n"
		"  type: %d, %d  active: %d, %d  position: %d, %d\n",
		name.c_str(), create, alter, relationName.c_str(), type.specified, type.value,
		active.specified, active.value, position.specified, position.value);

	if (external)
	{
		string s;
		s.printf("  external -> name: '%s'  engine: '%s'\n",
			external->name.c_str(), external->engine.c_str());
		text += s;
	}
}

DdlNode* CreateAlterTriggerNode::internalDsqlPass()
{
	DsqlCompiledStatement* statement = dsqlScratch->getStatement();
	statement->setBlockNode(this);
	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_TRIGGER);

	if (type.specified)
	{
		if (create &&	// ALTER TRIGGER doesn't accept table name
			((relationName.hasData() &&
				(type.value & (unsigned) TRIGGER_TYPE_MASK) != (unsigned) TRIGGER_TYPE_DML) ||
			 (relationName.isEmpty() &&
				(type.value & (unsigned) TRIGGER_TYPE_MASK) != (unsigned) TRIGGER_TYPE_DB &&
				(type.value & (unsigned) TRIGGER_TYPE_MASK) != (unsigned) TRIGGER_TYPE_DDL)))
		{
			status_exception::raise(
				Arg::Gds(isc_dsql_command_err) <<
				Arg::Gds(isc_dsql_incompatible_trigger_type));
		}
	}

	return DdlNode::internalDsqlPass();
}

void CreateAlterTriggerNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	fb_assert(create || alter);

	Attachment* attachment = transaction->getAttachment();

	if (relationName.isEmpty() && !attachment->locksmith())
		status_exception::raise(Arg::Gds(isc_adm_task_denied));

	source.ltrim("\n\r\t ");

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	if (!create)
	{
		AutoRequest requestHandle;

		FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
			TRG IN RDB$TRIGGERS
			WITH TRG.RDB$TRIGGER_NAME EQ name.c_str()
		{
			if (!type.specified && !TRG.RDB$TRIGGER_TYPE.NULL)
				type = TRG.RDB$TRIGGER_TYPE;

			if (relationName.isEmpty() && !TRG.RDB$RELATION_NAME.NULL)
				relationName = TRG.RDB$RELATION_NAME;
		}
		END_FOR

		if (!type.specified)
			status_exception::raise(Arg::Gds(isc_dyn_trig_not_found) << Arg::Str(name));
	}

	compile(tdbb, transaction);

	blrData = dsqlScratch->getBlrData();
	debugData = dsqlScratch->getDebugData();

	if (alter)
	{
		if (!modify(tdbb, transaction))
		{
			if (create)	// create or alter
				executeCreate(tdbb, transaction);
			else
				status_exception::raise(Arg::Gds(isc_dyn_trig_not_found) << Arg::Str(name));
		}
	}
	else
		executeCreate(tdbb, transaction);

	savePoint.release();	// everything is ok
}

void CreateAlterTriggerNode::executeCreate(thread_db* tdbb, jrd_tra* transaction)
{
	executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_TRIGGER, name);
	store(tdbb, transaction);
	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_CREATE_TRIGGER, name);
}

void CreateAlterTriggerNode::compile(thread_db* tdbb, jrd_tra* /*transaction*/)
{
	if (invalid)
		status_exception::raise(Arg::Gds(isc_dyn_invalid_ddl_trig) << name);

	if (compiled)
		return;

	compiled = true;
	invalid = true;

	if (body)
	{
		DsqlCompiledStatement* statement = dsqlScratch->getStatement();

		dsqlScratch->beginDebug();
		dsqlScratch->getBlrData().clear();

		// Create the "OLD" and "NEW" contexts for the trigger --
		// the new one could be a dummy place holder to avoid resolving
		// fields to that context but prevent relations referenced in
		// the trigger actions from referencing the predefined "1" context.
		if (dsqlScratch->contextNumber)
			resetContextStack();

		if (relationName.hasData())
		{
			dsql_nod* relationNode = FB_NEW_RPT(getPool(), e_rln_count) dsql_nod;
			///trigger_node->nod_arg[e_trg_table] = relationNode;
			relationNode->nod_type = nod_relation_name;
			relationNode->nod_count = e_rln_count;
			relationNode->nod_arg[e_rln_name] = (dsql_nod*)
				MAKE_string(relationName.c_str(), relationName.length());

			dsql_nod* const temp = relationNode->nod_arg[e_rln_alias];
			if (hasOldContext(type.value))
			{
				relationNode->nod_arg[e_rln_alias] = (dsql_nod*) MAKE_cstring(OLD_CONTEXT);
				dsql_ctx* oldContext = PASS1_make_context(dsqlScratch, relationNode);
				oldContext->ctx_flags |= CTX_system;
			}
			else
				dsqlScratch->contextNumber++;

			if (hasNewContext(type.value))
			{
				relationNode->nod_arg[e_rln_alias] = (dsql_nod*) MAKE_cstring(NEW_CONTEXT);
				dsql_ctx* newContext = PASS1_make_context(dsqlScratch, relationNode);
				newContext->ctx_flags |= CTX_system;
			}
			else
				dsqlScratch->contextNumber++;

			relationNode->nod_arg[e_rln_alias] = temp;
		}

		// generate the trigger blr

		if (statement->getFlags() & DsqlCompiledStatement::FLAG_BLR_VERSION4)
			dsqlScratch->appendUChar(blr_version4);
		else
			dsqlScratch->appendUChar(blr_version5);

		dsqlScratch->appendUChar(blr_begin);

		dsqlScratch->setPsql(true);

		putLocalVariables(dsqlScratch, localDeclList, 0);

		dsqlScratch->scopeLevel++;
		// dimitr: I see no reason to deny EXIT command in triggers,
		// hence I've added zero label at the beginning.
		// My first suspicion regarding an obvious conflict
		// with trigger messages (nod_abort) is wrong,
		// although the fact that they use the same BLR code
		// is still a potential danger and must be fixed.
		// Hopefully, system triggers are never recompiled.
		dsqlScratch->appendUChar(blr_label);
		dsqlScratch->appendUChar(0);
		dsqlScratch->loopLevel = 0;
		dsqlScratch->cursorNumber = 0;
		GEN_statement(dsqlScratch, PASS1_statement(dsqlScratch, body));
		dsqlScratch->scopeLevel--;
		dsqlScratch->appendUChar(blr_end);
		dsqlScratch->appendUChar(blr_eoc);

		dsqlScratch->endDebug();

		// The statement type may have been set incorrectly when parsing
		// the trigger actions, so reset it to reflect the fact that this
		// is a data definition statement; also reset the ddl node.
		statement->setType(DsqlCompiledStatement::TYPE_DDL);
	}

	invalid = false;
}


//----------------------


void DropTriggerNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropTriggerNode\n"
		"  name: '%s'\n",
		name.c_str());
}

DdlNode* DropTriggerNode::internalDsqlPass()
{
	dsqlScratch->flags |= (DsqlCompilerScratch::FLAG_BLOCK | DsqlCompilerScratch::FLAG_TRIGGER);
	return DdlNode::internalDsqlPass();
}

void DropTriggerNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	bool found = false;
	MetaName relationName;
	AutoCacheRequest requestHandle(tdbb, drq_e_trigger3, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		X IN RDB$TRIGGERS
		WITH X.RDB$TRIGGER_NAME EQ name.c_str()
	{
		if (!X.RDB$SYSTEM_FLAG.NULL)
		{
			switch (X.RDB$SYSTEM_FLAG)
			{
				case fb_sysflag_check_constraint:
				case fb_sysflag_referential_constraint:
				case fb_sysflag_view_check:
					status_exception::raise(Arg::Gds(isc_dyn_cant_modify_auto_trig));
					break;

				case fb_sysflag_system:
					status_exception::raise(
						Arg::Gds(isc_dyn_cannot_mod_systrig) << X.RDB$TRIGGER_NAME);
					break;

				default:
					break;
			}
		}

		if (X.RDB$RELATION_NAME.NULL && !transaction->getAttachment()->locksmith())
			status_exception::raise(Arg::Gds(isc_adm_task_denied));

		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_DROP_TRIGGER, name);

		relationName = X.RDB$RELATION_NAME;
		ERASE X;
		found = true;
	}
	END_FOR

	if (!found && !silent)
		status_exception::raise(Arg::Gds(isc_dyn_trig_not_found) << Arg::Str(name));

	requestHandle.reset(tdbb, drq_e_trg_msgs3, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		TM IN RDB$TRIGGER_MESSAGES
		WITH TM.RDB$TRIGGER_NAME EQ name.c_str()
	{
		ERASE TM;
	}
	END_FOR

	requestHandle.reset(tdbb, drq_e_trg_prv2, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		PRIV IN RDB$USER_PRIVILEGES
		WITH PRIV.RDB$USER EQ name.c_str() AND
			 PRIV.RDB$USER_TYPE = obj_trigger
	{
		ERASE PRIV;
	}
	END_FOR

	// Clear the update flags on the fields if this is the last remaining
	// trigger that changes a view.

	bool viewFound = false;
	requestHandle.reset(tdbb, drq_e_trg_prv3, DYN_REQUESTS);

	FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
		FIRST 1 V IN RDB$VIEW_RELATIONS
		CROSS F IN RDB$RELATION_FIELDS
		CROSS T IN RDB$TRIGGERS
		WITH V.RDB$VIEW_NAME EQ relationName.c_str() AND
			 F.RDB$RELATION_NAME EQ V.RDB$VIEW_NAME AND
			 F.RDB$RELATION_NAME EQ T.RDB$RELATION_NAME
	{
		viewFound = true;
	}
	END_FOR

	if (!viewFound)
	{
		requestHandle.reset(tdbb, drq_m_rel_flds2, DYN_REQUESTS);

		FOR (REQUEST_HANDLE requestHandle TRANSACTION_HANDLE transaction)
			F IN RDB$RELATION_FIELDS
			WITH F.RDB$RELATION_NAME EQ relationName.c_str()
		{
			MODIFY F USING
				F.RDB$UPDATE_FLAG = FALSE;
			END_MODIFY
		}
		END_FOR
	}

	if (found)
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_DROP_TRIGGER, name);

	savePoint.release();	// everything is ok
}


//----------------------


void RecreateTriggerNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf("RecreateTriggerNode\n");
}

DdlNode* RecreateTriggerNode::internalDsqlPass()
{
	dropNode.dsqlPass(dsqlScratch);
	createNode->dsqlPass(dsqlScratch);
	return DdlNode::internalDsqlPass();
}

void RecreateTriggerNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	dropNode.execute(tdbb, transaction);
	createNode->execute(tdbb, transaction);

	savePoint.release();	// everything is ok
}


//----------------------


void CreateCollationNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateCollationNode\n"
		"  name: '%s'\n"
		"  forCharSet: '%s'\n"
		"  fromName: '%s'\n"
		"  fromExternal: '%s'\n"
		"  attributesOn: %x\n"
		"  attributesOff: %x\n",
		name.c_str(), forCharSet.c_str(), fromName.c_str(), fromExternal.c_str(),
		attributesOn, attributesOff);
}

void CreateCollationNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->tra_attachment;

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_COLLATION, name);

	AutoCacheRequest request(tdbb, drq_s_colls, DYN_REQUESTS);

	STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$COLLATIONS
	{
		X.RDB$CHARACTER_SET_ID = forCharSetId;
		strcpy(X.RDB$COLLATION_NAME, name.c_str());
		X.RDB$SYSTEM_FLAG = 0;

		X.RDB$SPECIFIC_ATTRIBUTES.NULL = TRUE;
		X.RDB$BASE_COLLATION_NAME.NULL = TRUE;

		CharSet* cs = INTL_charset_lookup(tdbb, forCharSetId);
		SubtypeInfo info;

		if (fromName.hasData())
		{
			if (MET_get_char_coll_subtype_info(tdbb,
					INTL_CS_COLL_TO_TTYPE(forCharSetId, fromCollationId), &info) &&
				info.specificAttributes.hasData())
			{
				UCharBuffer temp;
				ULONG size = info.specificAttributes.getCount() * cs->maxBytesPerChar();

				size = INTL_convert_bytes(tdbb, forCharSetId, temp.getBuffer(size), size,
					CS_METADATA, info.specificAttributes.begin(),
					info.specificAttributes.getCount(), status_exception::raise);
				temp.shrink(size);
				info.specificAttributes = temp;
			}

			strcpy(X.RDB$BASE_COLLATION_NAME, info.baseCollationName.c_str());
			X.RDB$BASE_COLLATION_NAME.NULL = FALSE;
		}
		else if (fromExternal.hasData())
		{
			strcpy(X.RDB$BASE_COLLATION_NAME, fromExternal.c_str());
			X.RDB$BASE_COLLATION_NAME.NULL = FALSE;
		}

		if (specificAttributes.hasData())
		{
			UCharBuffer temp;
			ULONG size = specificAttributes.getCount() * cs->maxBytesPerChar();

			size = INTL_convert_bytes(tdbb, forCharSetId, temp.getBuffer(size), size,
				attachment->att_charset, specificAttributes.begin(),
				specificAttributes.getCount(), status_exception::raise);
			temp.shrink(size);
			specificAttributes = temp;
		}

		info.charsetName = forCharSet.c_str();
		info.collationName = name;
		if (X.RDB$BASE_COLLATION_NAME.NULL)
			info.baseCollationName = info.collationName;
		else
			info.baseCollationName = X.RDB$BASE_COLLATION_NAME;
		info.ignoreAttributes = false;

		if (!IntlManager::collationInstalled(info.baseCollationName.c_str(),
				info.charsetName.c_str()))
		{
			// msg: 223: "Collation @1 not installed for character set @2"
			status_exception::raise(
				Arg::Gds(ENCODE_ISC_MSG(223, DYN_MSG_FAC)) <<
				info.baseCollationName << info.charsetName);
		}

		IntlUtil::SpecificAttributesMap map;

		if (!IntlUtil::parseSpecificAttributes(
				cs, info.specificAttributes.getCount(), info.specificAttributes.begin(), &map) ||
			!IntlUtil::parseSpecificAttributes(
				cs, specificAttributes.getCount(), specificAttributes.begin(), &map))
		{
			// msg: 222: "Invalid collation attributes"
			status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(222, DYN_MSG_FAC)));
		}

		const string s = IntlUtil::generateSpecificAttributes(cs, map);
		string newSpecificAttributes;

		if (!IntlManager::setupCollationAttributes(
				info.baseCollationName.c_str(), info.charsetName.c_str(), s,
				newSpecificAttributes))
		{
			// msg: 222: "Invalid collation attributes"
			status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(222, DYN_MSG_FAC)));
		}

		memcpy(info.specificAttributes.getBuffer(newSpecificAttributes.length()),
			newSpecificAttributes.begin(), newSpecificAttributes.length());

		if (info.specificAttributes.hasData())
		{
			X.RDB$SPECIFIC_ATTRIBUTES.NULL = FALSE;
			attachment->storeMetaDataBlob(tdbb, transaction, &X.RDB$SPECIFIC_ATTRIBUTES,
				string(info.specificAttributes.begin(), info.specificAttributes.getCount()),
				forCharSetId);
		}

		info.attributes = (info.attributes | attributesOn) & (~attributesOff);
		X.RDB$COLLATION_ATTRIBUTES = info.attributes;

		// Do not allow invalid attributes here.
		if (!INTL_texttype_validate(tdbb, &info))
		{
			// msg: 222: "Invalid collation attributes"
			status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(222, DYN_MSG_FAC)));
		}

		// ASF: User collations are created with the last number available,
		// to minimize the possibility of conflicts with future system collations.
		// The greater available number is 126 to avoid signed/unsigned problems.

		X.RDB$COLLATION_ID.NULL = TRUE;
		X.RDB$COLLATION_ID = 126;

		AutoCacheRequest request2(tdbb, drq_l_max_coll_id, DYN_REQUESTS);

		FOR(REQUEST_HANDLE request2)
			Y IN RDB$COLLATIONS
			WITH Y.RDB$CHARACTER_SET_ID = forCharSetId AND
					Y.RDB$COLLATION_ID NOT MISSING
			SORTED BY DESCENDING Y.RDB$COLLATION_ID
		{
			if (Y.RDB$COLLATION_ID + 1 <= X.RDB$COLLATION_ID)
			{
				X.RDB$COLLATION_ID.NULL = FALSE;
				break;
			}
			else
				X.RDB$COLLATION_ID = Y.RDB$COLLATION_ID - 1;
		}
		END_FOR

		if (X.RDB$COLLATION_ID.NULL)
			status_exception::raise(Arg::Gds(isc_max_coll_per_charset));
	}
	END_STORE

	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_CREATE_COLLATION, name);

	savePoint.release();	// everything is ok

	// Update DSQL cache
	METD_drop_collation(transaction, name);
	MET_dsql_cache_release(tdbb, SYM_intlsym_collation, name);
}

DdlNode* CreateCollationNode::internalDsqlPass()
{
	const dsql_intlsym* resolvedCharSet = METD_get_charset(
		dsqlScratch->getTransaction(), forCharSet.length(), forCharSet.c_str());

	if (!resolvedCharSet)
	{
		// specified character set not found
		ERRD_post(Arg::Gds(isc_sqlerr) << Arg::Num(-504) <<
				  Arg::Gds(isc_charset_not_found) << forCharSet);
	}

	forCharSetId = resolvedCharSet->intlsym_charset_id;

	if (fromName.hasData())
	{
		const dsql_intlsym* resolvedCollation = METD_get_collation(
			dsqlScratch->getTransaction(), fromName, forCharSetId);

		if (!resolvedCollation)
		{
			// Specified collation not found
			ERRD_post(Arg::Gds(isc_sqlerr) << Arg::Num(-204) <<
					  Arg::Gds(isc_collation_not_found) << fromName << forCharSet);
		}

		fromCollationId = resolvedCollation->intlsym_collate_id;
	}

	return DdlNode::internalDsqlPass();
}


//----------------------


void DropCollationNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropCollationNode\n"
		"  name: '%s'\n",
		name.c_str());
}

void DropCollationNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	bool found = false;
	AutoCacheRequest request(tdbb, drq_e_colls, DYN_REQUESTS);

	FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		COLL IN RDB$COLLATIONS
		CROSS CS IN RDB$CHARACTER_SETS
		WITH COLL.RDB$COLLATION_NAME EQ name.c_str() AND
			 CS.RDB$CHARACTER_SET_ID EQ COLL.RDB$CHARACTER_SET_ID
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_DROP_COLLATION, name);

		if (!COLL.RDB$SYSTEM_FLAG.NULL && COLL.RDB$SYSTEM_FLAG)
			status_exception::raise(Arg::Gds(isc_dyn_cannot_del_syscoll));

		if (COLL.RDB$COLLATION_ID == 0 ||
			(!CS.RDB$DEFAULT_COLLATE_NAME.NULL &&
				MetaName(COLL.RDB$COLLATION_NAME) == MetaName(CS.RDB$DEFAULT_COLLATE_NAME)))
		{
			fb_utils::exact_name_limit(CS.RDB$CHARACTER_SET_NAME,
				sizeof(CS.RDB$CHARACTER_SET_NAME));

			status_exception::raise(
				Arg::Gds(isc_dyn_cannot_del_def_coll) << CS.RDB$CHARACTER_SET_NAME);
		}

		found = true;
		fb_utils::exact_name_limit(COLL.RDB$COLLATION_NAME, sizeof(COLL.RDB$COLLATION_NAME));

		AutoCacheRequest request2(tdbb, drq_l_rfld_coll, DYN_REQUESTS);

		FOR (REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
			RF IN RDB$RELATION_FIELDS CROSS F IN RDB$FIELDS
			WITH RF.RDB$FIELD_SOURCE EQ F.RDB$FIELD_NAME AND
				 F.RDB$CHARACTER_SET_ID EQ COLL.RDB$CHARACTER_SET_ID AND
				 RF.RDB$COLLATION_ID EQ COLL.RDB$COLLATION_ID
		{
			fb_utils::exact_name_limit(RF.RDB$RELATION_NAME, sizeof(RF.RDB$RELATION_NAME));
			fb_utils::exact_name_limit(RF.RDB$FIELD_NAME, sizeof(RF.RDB$FIELD_NAME));

			status_exception::raise(
				Arg::Gds(isc_dyn_coll_used_table) << COLL.RDB$COLLATION_NAME <<
				RF.RDB$RELATION_NAME << RF.RDB$FIELD_NAME);
		}
		END_FOR

		request2.reset(tdbb, drq_l_prm_coll, DYN_REQUESTS);

		FOR (REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
			PRM IN RDB$PROCEDURE_PARAMETERS CROSS F IN RDB$FIELDS
			WITH PRM.RDB$FIELD_SOURCE EQ F.RDB$FIELD_NAME AND
				 F.RDB$CHARACTER_SET_ID EQ COLL.RDB$CHARACTER_SET_ID AND
				 PRM.RDB$COLLATION_ID EQ COLL.RDB$COLLATION_ID
		{
			fb_utils::exact_name_limit(PRM.RDB$PARAMETER_NAME, sizeof(PRM.RDB$PARAMETER_NAME));

			status_exception::raise(
				Arg::Gds(isc_dyn_coll_used_procedure) <<
				COLL.RDB$COLLATION_NAME <<
				QualifiedName(PRM.RDB$PROCEDURE_NAME,
					(PRM.RDB$PACKAGE_NAME.NULL ? NULL : PRM.RDB$PACKAGE_NAME)).toString().c_str() <<
				PRM.RDB$PARAMETER_NAME);
		}
		END_FOR

		request2.reset(tdbb, drq_l_fld_coll, DYN_REQUESTS);

		FOR (REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
			F IN RDB$FIELDS
			WITH F.RDB$CHARACTER_SET_ID EQ COLL.RDB$CHARACTER_SET_ID AND
				 F.RDB$COLLATION_ID EQ COLL.RDB$COLLATION_ID
		{
			fb_utils::exact_name_limit(F.RDB$FIELD_NAME, sizeof(F.RDB$FIELD_NAME));

			status_exception::raise(
				Arg::Gds(isc_dyn_coll_used_domain) << COLL.RDB$COLLATION_NAME << F.RDB$FIELD_NAME);
		}
		END_FOR

		ERASE COLL;
	}
	END_FOR

	if (found)
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_DROP_COLLATION, name);
	else
		status_exception::raise(Arg::Gds(isc_dyn_collation_not_found) << Arg::Str(name));

	savePoint.release();	// everything is ok

	// Update DSQL cache
	METD_drop_collation(transaction, name);
	MET_dsql_cache_release(tdbb, SYM_intlsym_collation, name);
}


//----------------------


void CreateDomainNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	string nameTypeStr;
	nameType.print(nameTypeStr);

	text =
		"CreateDomainNode\n"
		"  " + nameTypeStr + "\n";
}

void CreateDomainNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->tra_attachment;

	if (fb_utils::implicit_domain(nameType.name.c_str()))
	{
		status_exception::raise(
			Arg::Gds(isc_sqlerr) << Arg::Num(-637) <<
			Arg::Gds(isc_dsql_implicit_domain_name) << nameType.name);
	}

	const dsql_nod* elements = nameType.legacyField->fld_ranges;
	const USHORT dims = elements ? elements->nod_count / 2 : 0;

	if (nameType.legacyDefault && dims != 0)
	{
		// Default value is not allowed for array type in domain %s
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(226, DYN_MSG_FAC)) << nameType.name);
	}

	nameType.resolve(dsqlScratch);

	dsqlScratch->domainValue.dsc_dtype = nameType.type;
	dsqlScratch->domainValue.dsc_length = nameType.length;
	dsqlScratch->domainValue.dsc_scale = nameType.scale;

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_DOMAIN, nameType.name);

	storeGlobalField(tdbb, transaction, nameType.name, nameType);

	if (nameType.legacyDefault || check || notNull)
	{
		AutoCacheRequest request(tdbb, drq_m_fld, DYN_REQUESTS);

		FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			FLD IN RDB$FIELDS
			WITH FLD.RDB$FIELD_NAME EQ nameType.name.c_str()
		{
			MODIFY FLD
				if (nameType.legacyDefault)
				{
					dsql_str* defaultString =
						(dsql_str*) nameType.legacyDefault->nod_arg[e_dft_default_source];
					string defaultSource = string(defaultString->str_data, defaultString->str_length);

					FLD.RDB$DEFAULT_SOURCE.NULL = FALSE;
					attachment->storeMetaDataBlob(tdbb, transaction, &FLD.RDB$DEFAULT_SOURCE, defaultSource);

					dsqlScratch->getBlrData().clear();
					dsqlScratch->appendUChar(dsqlScratch->isVersion4() ? blr_version4 : blr_version5);

					dsql_nod* node = PASS1_node(dsqlScratch, nameType.legacyDefault->nod_arg[e_dft_default]);

					GEN_hidden_variables(dsqlScratch, true);
					GEN_expr(dsqlScratch, node);

					dsqlScratch->appendUChar(blr_eoc);

					FLD.RDB$DEFAULT_VALUE.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &FLD.RDB$DEFAULT_VALUE,
						dsqlScratch->getBlrData());
				}

				if (check)
				{
					dsql_str* checkString = (dsql_str*) check->nod_arg[e_cnstr_source];
					string checkSource = string(checkString->str_data, checkString->str_length);

					FLD.RDB$VALIDATION_SOURCE.NULL = FALSE;
					attachment->storeMetaDataBlob(tdbb, transaction, &FLD.RDB$VALIDATION_SOURCE, checkSource);

					dsqlScratch->getBlrData().clear();
					dsqlScratch->appendUChar(dsqlScratch->isVersion4() ? blr_version4 : blr_version5);

					// Increment the context level for this statement, so that the context number for
					// any RSE generated for a SELECT within the CHECK clause will be greater than 0.
					// In the environment of a domain check constraint, context number 0 is reserved
					// for the "blr_fid, 0, 0, 0," which is emitted for a nod_dom_value, corresponding
					// to an occurance of the VALUE keyword in the body of the check constraint.
					// -- chrisj 1999-08-20
					++dsqlScratch->contextNumber;

					dsql_nod* node = PASS1_node(dsqlScratch, check->nod_arg[e_cnstr_condition]);

					GEN_hidden_variables(dsqlScratch, true);
					GEN_expr(dsqlScratch, node);

					dsqlScratch->appendUChar(blr_eoc);

					FLD.RDB$VALIDATION_BLR.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &FLD.RDB$VALIDATION_BLR,
						dsqlScratch->getBlrData());
				}

				if (notNull)
				{
					FLD.RDB$NULL_FLAG.NULL = FALSE;
					FLD.RDB$NULL_FLAG = 1;
				}
			END_MODIFY
		}
		END_FOR
	}

	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_CREATE_DOMAIN, nameType.name);

	savePoint.release();	// everything is ok
}


//----------------------


// Compare the original field type with the new field type to determine if the original type can be
// changed to the new type.
//
// The following conversions are not allowed:
//   Blob to anything
//   Array to anything
//   Date to anything
//   Char to any numeric
//   Varchar to any numeric
//   Anything to Blob
//   Anything to Array
//
// This function throws an exception if the conversion can not be made.
//
// ASF: We should stop using dyn_fld here as soon DYN stops to be a caller of this function.
void AlterDomainNode::checkUpdate(const dyn_fld& origFld, const dyn_fld& newFld)
{
	ULONG errorCode = FB_SUCCESS;

	// Check to make sure that the old and new types are compatible
	switch (origFld.dyn_dtype)
	{
	// CHARACTER types
	case blr_text:
	case blr_varying:
	case blr_cstring:
		switch (newFld.dyn_dtype)
		{
		case blr_blob:
		case blr_blob_id:
			// Cannot change datatype for column %s.
			// The operation cannot be performed on BLOB, or ARRAY columns.
			errorCode = isc_dyn_dtype_invalid;
			break;

		case blr_sql_date:
		case blr_sql_time:
		case blr_timestamp:
		case blr_int64:
		case blr_long:
		case blr_short:
		case blr_d_float:
		case blr_double:
		case blr_float:
			// Cannot convert column %s from character to non-character data.
			errorCode = isc_dyn_dtype_conv_invalid;
			break;

		// If the original field is a character field and the new field is a character field,
		// is there enough space in the new field?
		case blr_text:
		case blr_varying:
		case blr_cstring:
			{
				// CVC: Because our caller invoked DSC_make_descriptor() on newFld previously,
				// we should have the added bytes for varchar. For cstring, we are done, since
				// DSC_make_descriptor(DSC_string_length) != DSC_string_length(DSC_make_descriptor).

				const USHORT maxflen = DSC_string_length(&origFld.dyn_dsc);

				// We can have this assertion since this case is for both string fields.
				const ULONG new_len = DSC_string_length(&newFld.dyn_dsc);
				fb_assert(new_len - maxflen == (ULONG) newFld.dyn_charbytelen - origFld.dyn_charbytelen);
				// if (newFld.dyn_dsc.dsc_length < maxflen)
				if (new_len < maxflen)
				{
					// msg 208: New size specified for column %s must be at least %d characters.
					errorCode = isc_dyn_char_fld_too_small;
				}
			}
			break;

		default:
			fb_assert(FALSE);
			errorCode = 87;			// MODIFY RDB$FIELDS FAILED
			break;
		}
		break;

	// BLOB and ARRAY types
	case blr_blob:
	case blr_blob_id:
		// Cannot change datatype for column %s.
		// The operation cannot be performed on BLOB, or ARRAY columns.
		errorCode = isc_dyn_dtype_invalid;
		break;

	// DATE types
	case blr_sql_date:
	case blr_sql_time:
	case blr_timestamp:
		switch (newFld.dyn_dtype)
		{
		case blr_sql_date:
			if (origFld.dyn_dtype == blr_sql_time)
			{
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
			}
			break;

		case blr_sql_time:
			if (origFld.dyn_dtype == blr_sql_date)
			{
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
			}
			break;

		case blr_timestamp:
			if (origFld.dyn_dtype == blr_sql_time)
			{
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
			}
			break;

		// If the original field is a date field and the new field is a character field,
		// is there enough space in the new field?
		case blr_text:
		case blr_text2:
		case blr_varying:
		case blr_varying2:
		case blr_cstring:
		case blr_cstring2:
			{
				const USHORT maxflen = DSC_string_length(&origFld.dyn_dsc);

				// CVC: Solve bug #910423, missing DSC_string_length call.
				// if (newFld.dyn_dsc.dsc_length < maxflen)
				if (DSC_string_length(&newFld.dyn_dsc) < maxflen)
				{
					// msg 208: New size specified for column %s must be at least %d characters.
					errorCode = isc_dyn_char_fld_too_small;
				}
			}

			break;

		default:
			// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
			errorCode = isc_dyn_invalid_dtype_conversion;
			break;
		}
		break;

	// NUMERIC types
	case blr_int64:
	case blr_long:
	case blr_short:
	case blr_d_float:
	case blr_double:
	case blr_float:
		switch (newFld.dyn_dtype)
		{
		case blr_blob:
		case blr_blob_id:
			// Cannot change datatype for column %s.
			// The operation cannot be performed on BLOB, or ARRAY columns.
			errorCode = isc_dyn_dtype_invalid;
			break;

		case blr_sql_date:
		case blr_sql_time:
		case blr_timestamp:
			// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
			errorCode = isc_dyn_invalid_dtype_conversion;
			break;

		// If the original field is a numeric field and the new field is a numeric field,
		// is there enough space in the new field (do not allow the base type to decrease)

		case blr_short:
			switch (origFld.dyn_dtype)
			{
			case blr_short:
				errorCode = checkUpdateNumericType(origFld, newFld);
				break;

			default:
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
				break;
			}
			break;

		case blr_long:
			switch (origFld.dyn_dtype)
			{
			case blr_long:
			case blr_short:
				errorCode = checkUpdateNumericType(origFld, newFld);
				break;

			default:
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
				break;
			}
			break;

		case blr_float:
			switch (origFld.dyn_dtype)
			{
			case blr_float:
			case blr_short:
				break;

			default:
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
				break;
			}
			break;

		case blr_int64:
			switch (origFld.dyn_dtype)
			{
			case blr_int64:
			case blr_long:
			case blr_short:
				errorCode = checkUpdateNumericType(origFld, newFld);
				break;

			default:
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
				break;
			}
			break;

		case blr_d_float:
		case blr_double:
			switch (origFld.dyn_dtype)
			{
			case blr_double:
			case blr_d_float:
			case blr_float:
			case blr_short:
			case blr_long:
				break;

			default:
				// Cannot change datatype for column %s.  Conversion from base type %s to base type %s is not supported.
				errorCode = isc_dyn_invalid_dtype_conversion;
				break;
			}
			break;

		// If the original field is a numeric field and the new field is a character field,
		// is there enough space in the new field?
		case blr_text:
		case blr_varying:
		case blr_cstring:
			{
				const USHORT maxflen = DSC_string_length(&origFld.dyn_dsc);

				// CVC: Solve bug #910423, missing DSC_string_length call.
				// if (newFld.dyn_dsc.dsc_length < maxflen)
				if (DSC_string_length(&newFld.dyn_dsc) < maxflen)
				{
					// msg 208: New size specified for column %s must be at least %d characters.
					errorCode = isc_dyn_char_fld_too_small;
				}
			}
			break;

		default:
			fb_assert(FALSE);
			errorCode = 87;			// MODIFY RDB$FIELDS FAILED
			break;
		}
		break;

	default:
		fb_assert(FALSE);
		errorCode = 87;				// MODIFY RDB$FIELDS FAILED
		break;
	}

	if (errorCode == FB_SUCCESS)
		return;

	switch (errorCode)
	{
	case isc_dyn_dtype_invalid:
		// Cannot change datatype for column %s.The operation cannot be performed on DATE, BLOB, or ARRAY columns.
		status_exception::raise(Arg::Gds(errorCode) << origFld.dyn_fld_name.c_str());
		break;

	case isc_dyn_dtype_conv_invalid:
		// Cannot convert column %s from character to non-character data.
		status_exception::raise(Arg::Gds(errorCode) << origFld.dyn_fld_name.c_str());
		break;

	case isc_dyn_char_fld_too_small:
		// msg 208: New size specified for column %s must be at least %d characters.
		status_exception::raise(
			Arg::Gds(errorCode) << origFld.dyn_fld_name.c_str() <<
				Arg::Num(DSC_string_length(&origFld.dyn_dsc)));
		break;

	case isc_dyn_scale_too_big:
		{
			int code = errorCode;
			int diff = newFld.dyn_precision -
				(origFld.dyn_precision + origFld.dyn_dsc.dsc_scale);
			if (diff < 0)
			{
				// If new scale becomes negative externally, the message is useless for the user.
				// (The scale is always zero or negative for us but externally is non-negative.)
				// Let's ask the user to widen the precision, then. Example: numeric(4, 0) -> numeric(1, 1).
				code = isc_dyn_precision_too_small;
				diff = newFld.dyn_precision - newFld.dyn_dsc.dsc_scale - diff;
			}

			// scale_too_big: New scale specified for column @1 must be at most @2.
			// precision_too_small: New precision specified for column @1 must be at least @2.
			status_exception::raise(
				Arg::Gds(code) << origFld.dyn_fld_name.c_str() << Arg::Num(diff));
		}
		break;

	case isc_dyn_invalid_dtype_conversion:
		{
			TEXT orig_type[25], new_type[25];

			DSC_get_dtype_name(&origFld.dyn_dsc, orig_type, sizeof(orig_type));
			DSC_get_dtype_name(&newFld.dyn_dsc, new_type, sizeof(new_type));

			// Cannot change datatype for @1.  Conversion from base type @2 to @3 is not supported.
			status_exception::raise(
				Arg::Gds(errorCode) << origFld.dyn_fld_name.c_str() << orig_type << new_type);
		}
		break;

	default:
		// msg 95: "MODIFY RDB$RELATION_FIELDS failed"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(95, DYN_MSG_FAC)));
	}
}

// Compare the original field type with the new field type to determine if the original type can be
// changed to the new type.
// The types should be integral, since it tests only numeric/decimal subtypes to ensure the scale is
// not being widened at the expense of the precision, because the old stored values should fit in
// the new definition.
//
// This function returns an error code if the conversion can not be made. If the conversion can be
// made, FB_SUCCESS is returned.
ULONG AlterDomainNode::checkUpdateNumericType(const dyn_fld& origFld, const dyn_fld& newFld)
{
 	// Since dsc_scale is negative, the sum of precision and scale produces
	// the width of the integral part.
	if (origFld.dyn_sub_type && newFld.dyn_sub_type &&
		origFld.dyn_precision + origFld.dyn_dsc.dsc_scale >
			newFld.dyn_precision + newFld.dyn_dsc.dsc_scale)
	{
		return isc_dyn_scale_too_big;
	}

	return FB_SUCCESS;
}

// Retrieves the type information for a domain so that it can be compared to a local field before
// modifying the datatype of a field.
void AlterDomainNode::getDomainType(thread_db* tdbb, jrd_tra* transaction, dyn_fld& dynFld)
{
	AutoRequest request;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$FIELDS
		WITH FLD.RDB$FIELD_NAME EQ dynFld.dyn_fld_source.c_str();
	{
		DSC_make_descriptor(&dynFld.dyn_dsc, FLD.RDB$FIELD_TYPE, FLD.RDB$FIELD_SCALE,
			FLD.RDB$FIELD_LENGTH, FLD.RDB$FIELD_SUB_TYPE, FLD.RDB$CHARACTER_SET_ID,
			FLD.RDB$COLLATION_ID);

		dynFld.dyn_charbytelen = FLD.RDB$FIELD_LENGTH;
		dynFld.dyn_dtype = FLD.RDB$FIELD_TYPE;
		dynFld.dyn_precision = FLD.RDB$FIELD_PRECISION;
		dynFld.dyn_sub_type = FLD.RDB$FIELD_SUB_TYPE;
		dynFld.dyn_charlen = FLD.RDB$CHARACTER_LENGTH;
		dynFld.dyn_collation = FLD.RDB$COLLATION_ID;
		dynFld.dyn_null_flag = FLD.RDB$NULL_FLAG != 0;

		if (!FLD.RDB$DIMENSIONS.NULL && FLD.RDB$DIMENSIONS > 0)
			dynFld.dyn_dtype = blr_blob;
	}
	END_FOR
}

// Updates the field names in an index and forces the index to be rebuilt with the new field names.
void AlterDomainNode::modifyLocalFieldIndex(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName, const MetaName& newFieldName)
{
	AutoRequest request;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDX IN RDB$INDICES CROSS IDXS IN RDB$INDEX_SEGMENTS WITH
			IDX.RDB$INDEX_NAME EQ IDXS.RDB$INDEX_NAME AND
			IDX.RDB$RELATION_NAME EQ relationName.c_str() AND
			IDXS.RDB$FIELD_NAME EQ fieldName.c_str()
	{
		// Change the name of the field in the index
		MODIFY IDXS USING
			memcpy(IDXS.RDB$FIELD_NAME, newFieldName.c_str(), sizeof(IDXS.RDB$FIELD_NAME));
		END_MODIFY

		// Set the index name to itself to tell the index to rebuild
		MODIFY IDX USING
			// This is to fool both gpre and gcc.
			char* p = IDX.RDB$INDEX_NAME;
			p[MAX_SQL_IDENTIFIER_LEN] = 0;
		END_MODIFY
	}
	END_FOR
}

void AlterDomainNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"AlterDomainNode\n"
		"  %s\n", name.c_str());
}

void AlterDomainNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->tra_attachment;

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	AutoCacheRequest request(tdbb, drq_m_fld2, DYN_REQUESTS);
	bool found = false;

	FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$FIELDS
		WITH FLD.RDB$FIELD_NAME EQ name.c_str()
	{
		found = true;
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_DOMAIN, name);

		MODIFY FLD
			if (dropConstraint)
			{
				FLD.RDB$VALIDATION_BLR.NULL = TRUE;
				FLD.RDB$VALIDATION_SOURCE.NULL = TRUE;
			}

			if (dropDefault)
			{
				FLD.RDB$DEFAULT_VALUE.NULL = TRUE;
				FLD.RDB$DEFAULT_SOURCE.NULL = TRUE;
			}

			if (setConstraint)
			{
				if (!FLD.RDB$VALIDATION_BLR.NULL)
				{
					// msg 160: "Only one constraint allowed for a domain"
					status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(160, DYN_MSG_FAC)));
				}

				dsql_fld localField(dsqlScratch->getStatement()->getPool());

				// Get the attributes of the domain, and set any occurances of
				// keyword VALUE to the correct type, length, scale, etc.
				if (!METD_get_domain(dsqlScratch->getTransaction(), &localField, name.c_str()))
				{
					// Specified domain or source field does not exist
					status_exception::raise(
						Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
						Arg::Gds(isc_dsql_command_err) <<
						Arg::Gds(isc_dsql_domain_not_found) << name);
				}

				dsqlScratch->domainValue.dsc_dtype = localField.fld_dtype;
				dsqlScratch->domainValue.dsc_length = localField.fld_length;
				dsqlScratch->domainValue.dsc_scale = localField.fld_scale;

				dsql_str* checkString = (dsql_str*) setConstraint->nod_arg[e_cnstr_source];
				string checkSource = string(checkString->str_data, checkString->str_length);

				FLD.RDB$VALIDATION_SOURCE.NULL = FALSE;
				attachment->storeMetaDataBlob(tdbb, transaction, &FLD.RDB$VALIDATION_SOURCE, checkSource);

				dsqlScratch->getBlrData().clear();
				dsqlScratch->appendUChar(dsqlScratch->isVersion4() ? blr_version4 : blr_version5);

				// Increment the context level for this statement, so that the context number for
				// any RSE generated for a SELECT within the CHECK clause will be greater than 0.
				// In the environment of a domain check constraint, context number 0 is reserved
				// for the "blr_fid, 0, 0, 0," which is emitted for a nod_dom_value, corresponding
				// to an occurance of the VALUE keyword in the body of the check constraint.
				// -- chrisj 1999-08-20
				++dsqlScratch->contextNumber;

				dsql_nod* node = PASS1_node(dsqlScratch, setConstraint->nod_arg[e_cnstr_condition]);

				GEN_hidden_variables(dsqlScratch, true);
				GEN_expr(dsqlScratch, node);

				dsqlScratch->appendUChar(blr_eoc);

				FLD.RDB$VALIDATION_BLR.NULL = FALSE;
				attachment->storeBinaryBlob(tdbb, transaction, &FLD.RDB$VALIDATION_BLR,
					dsqlScratch->getBlrData());
			}

			if (setDefault)
			{
				if (FLD.RDB$DIMENSIONS)
				{
					// msg 226: "Default value is not allowed for array type in domain %s"
					status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(226, DYN_MSG_FAC)) << name);
				}

				dsql_str* defaultString =
					(dsql_str*) setDefault->nod_arg[e_dft_default_source];
				string defaultSource = string(defaultString->str_data, defaultString->str_length);

				FLD.RDB$DEFAULT_SOURCE.NULL = FALSE;
				attachment->storeMetaDataBlob(tdbb, transaction, &FLD.RDB$DEFAULT_SOURCE, defaultSource);

				dsqlScratch->getBlrData().clear();
				dsqlScratch->appendUChar(dsqlScratch->isVersion4() ? blr_version4 : blr_version5);

				dsql_nod* node = PASS1_node(dsqlScratch, setDefault->nod_arg[e_dft_default]);

				GEN_hidden_variables(dsqlScratch, true);
				GEN_expr(dsqlScratch, node);

				dsqlScratch->appendUChar(blr_eoc);

				FLD.RDB$DEFAULT_VALUE.NULL = FALSE;
				attachment->storeBinaryBlob(tdbb, transaction, &FLD.RDB$DEFAULT_VALUE,
					dsqlScratch->getBlrData());
			}

			if (nullFlag.specified)
			{
				FLD.RDB$NULL_FLAG.NULL = FALSE;
				FLD.RDB$NULL_FLAG = nullFlag.value ? 0 : 1;
			}

			if (type)
			{
				type->resolve(dsqlScratch);

				dyn_fld origDom, newDom;

				DSC_make_descriptor(&origDom.dyn_dsc, FLD.RDB$FIELD_TYPE, FLD.RDB$FIELD_SCALE,
					FLD.RDB$FIELD_LENGTH, FLD.RDB$FIELD_SUB_TYPE, FLD.RDB$CHARACTER_SET_ID,
					FLD.RDB$COLLATION_ID);

				origDom.dyn_fld_name = name;
				origDom.dyn_charbytelen = FLD.RDB$FIELD_LENGTH;
				origDom.dyn_dtype = FLD.RDB$FIELD_TYPE;
				origDom.dyn_precision = FLD.RDB$FIELD_PRECISION;
				origDom.dyn_sub_type = FLD.RDB$FIELD_SUB_TYPE;
				origDom.dyn_charlen = FLD.RDB$CHARACTER_LENGTH;
				origDom.dyn_collation = FLD.RDB$COLLATION_ID;
				origDom.dyn_null_flag = !FLD.RDB$NULL_FLAG.NULL && FLD.RDB$NULL_FLAG != 0;

				// If the original field type is an array, force its blr type to blr_blob
				if (FLD.RDB$DIMENSIONS != 0)
					origDom.dyn_dtype = blr_blob;

				USHORT typeLength = type->length;
				switch (type->type)
				{
					case dtype_varying:
						typeLength -= sizeof(USHORT);
						break;

					// Not valid for domains, but may be important for a future refactor.
					case dtype_cstring:
						--typeLength;
						break;

					default:
						break;
				}

				DSC_make_descriptor(&newDom.dyn_dsc, blr_dtypes[type->type], type->scale,
					typeLength, type->subType, type->charSetId, type->collationId);

				newDom.dyn_fld_name = name;
				newDom.dyn_charbytelen = typeLength;
				newDom.dyn_dtype = blr_dtypes[type->type];
				newDom.dyn_precision = type->precision;
				newDom.dyn_sub_type = type->subType;
				newDom.dyn_charlen = type->charLength;
				newDom.dyn_collation = type->collationId;
				newDom.dyn_null_flag = type->notNull;

				// Now that we have all of the information needed, let's check to see if the field
				// type can be modifed.

				checkUpdate(origDom, newDom);

				if (!newDom.dyn_dsc.isExact() || newDom.dyn_dsc.dsc_scale != 0)
				{
					AutoCacheRequest request(tdbb, drq_l_ident_gens, DYN_REQUESTS);

					FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
						RFR IN RDB$RELATION_FIELDS
						WITH RFR.RDB$FIELD_SOURCE = FLD.RDB$FIELD_NAME AND
								RFR.RDB$GENERATOR_NAME NOT MISSING
					{
						// Domain @1 must be of exact number type with zero scale because it's used
						// in an identity column.
						status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(276, DYN_MSG_FAC)) << name);
					}
					END_FOR
				}

				// If the datatype was changed, update any indexes that involved the domain

				AutoRequest request2;

				FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
					DOM IN RDB$RELATION_FIELDS
					WITH DOM.RDB$FIELD_SOURCE EQ name.c_str()
				{
					modifyLocalFieldIndex(tdbb, transaction, DOM.RDB$RELATION_NAME,
						DOM.RDB$FIELD_NAME, DOM.RDB$FIELD_NAME);
				}
				END_FOR

				// Update RDB$FIELDS
				updateRdbFields(*type,
					FLD.RDB$FIELD_TYPE,
					FLD.RDB$FIELD_LENGTH,
					FLD.RDB$FIELD_SUB_TYPE.NULL, FLD.RDB$FIELD_SUB_TYPE,
					FLD.RDB$FIELD_SCALE.NULL, FLD.RDB$FIELD_SCALE,
					FLD.RDB$CHARACTER_SET_ID.NULL, FLD.RDB$CHARACTER_SET_ID,
					FLD.RDB$CHARACTER_LENGTH.NULL, FLD.RDB$CHARACTER_LENGTH,
					FLD.RDB$FIELD_PRECISION.NULL, FLD.RDB$FIELD_PRECISION,
					FLD.RDB$COLLATION_ID.NULL, FLD.RDB$COLLATION_ID,
					FLD.RDB$SEGMENT_LENGTH.NULL, FLD.RDB$SEGMENT_LENGTH);
			}

			if (renameTo.hasData())
			{
				rename(tdbb, transaction, (FLD.RDB$DIMENSIONS.NULL ? 0 : FLD.RDB$DIMENSIONS));
				strcpy(FLD.RDB$FIELD_NAME, renameTo.c_str());
			}
		END_MODIFY
	}
	END_FOR

	if (!found)
	{
		// msg 89: "Global field not found"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(89, DYN_MSG_FAC)));
	}

	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_ALTER_DOMAIN, name);

	savePoint.release();	// everything is ok
}

void AlterDomainNode::rename(thread_db* tdbb, jrd_tra* transaction, SSHORT dimensions)
{
	// Checks to see if the given domain already exists.

	AutoRequest request;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$FIELDS WITH FLD.RDB$FIELD_NAME EQ renameTo.c_str()
	{
		// msg 204: Cannot rename domain %s to %s.  A domain with that name already exists.
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(204, DYN_MSG_FAC)) << name << renameTo);
	}
	END_FOR

	// CVC: Let's update the dimensions, too.
	if (dimensions != 0)
	{
		request.reset();

		FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			FDIM IN RDB$FIELD_DIMENSIONS
			WITH FDIM.RDB$FIELD_NAME EQ name.c_str()
		{
			MODIFY FDIM USING
				strcpy(FDIM.RDB$FIELD_NAME, renameTo.c_str());
			END_MODIFY
		}
		END_FOR
	}

	request.reset();

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		RFLD IN RDB$RELATION_FIELDS
		WITH RFLD.RDB$FIELD_SOURCE EQ name.c_str()
	{
		MODIFY RFLD USING
			strcpy(RFLD.RDB$FIELD_SOURCE, renameTo.c_str());
		END_MODIFY

		modifyLocalFieldIndex(tdbb, transaction, RFLD.RDB$RELATION_NAME,
			RFLD.RDB$FIELD_NAME, RFLD.RDB$FIELD_NAME);
	}
	END_FOR
}


//----------------------


// Delete the records in RDB$FIELD_DIMENSIONS pertaining to a field.
bool DropDomainNode::deleteDimensionRecords(thread_db* tdbb, jrd_tra* transaction, const MetaName& name)
{
	AutoCacheRequest request(tdbb, drq_e_dims, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$FIELD_DIMENSIONS
		WITH X.RDB$FIELD_NAME EQ name.c_str()
	{
		found = true;
		ERASE X;
	}
	END_FOR

	return found;
}

void DropDomainNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropDomainNode\n"
		"  name: '%s'\n",
		name.c_str());
}

void DropDomainNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	AutoCacheRequest request(tdbb, drq_e_gfields, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$FIELDS
		WITH X.RDB$FIELD_NAME EQ name.c_str()
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_DROP_DOMAIN, name);

		check(tdbb, transaction);
		deleteDimensionRecords(tdbb, transaction, name);

		ERASE X;

		found = true;
	}
	END_FOR

	if (found)
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_DROP_DOMAIN, name);
	else
	{
		// msg 89: "Domain not found"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(89, DYN_MSG_FAC)));
	}

	savePoint.release();	// everything is ok
}

void DropDomainNode::check(thread_db* tdbb, jrd_tra* transaction)
{
	AutoCacheRequest request(tdbb, drq_l_fld_src, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		Y IN RDB$RELATION_FIELDS
		WITH Y.RDB$FIELD_SOURCE EQ name.c_str()
	{
		fb_utils::exact_name_limit(Y.RDB$FIELD_SOURCE, sizeof(Y.RDB$FIELD_SOURCE));
		fb_utils::exact_name_limit(Y.RDB$RELATION_NAME, sizeof(Y.RDB$RELATION_NAME));
		fb_utils::exact_name_limit(Y.RDB$FIELD_NAME, sizeof(Y.RDB$FIELD_NAME));

		// msg 43: "Domain %s is used in table %s (local name %s) and can not be dropped"
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(43, DYN_MSG_FAC)) << Y.RDB$FIELD_SOURCE <<
				Y.RDB$RELATION_NAME << Y.RDB$FIELD_NAME);
	}
	END_FOR

	request.reset(tdbb, drq_l_prp_src, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$PROCEDURE_PARAMETERS
		WITH X.RDB$FIELD_SOURCE EQ name.c_str()
	{
		fb_utils::exact_name_limit(X.RDB$FIELD_SOURCE, sizeof(X.RDB$FIELD_SOURCE));
		fb_utils::exact_name_limit(X.RDB$PROCEDURE_NAME, sizeof(X.RDB$PROCEDURE_NAME));
		fb_utils::exact_name_limit(X.RDB$PARAMETER_NAME, sizeof(X.RDB$PARAMETER_NAME));

		// msg 239: "Domain %s is used in procedure %s (parameter name %s) and cannot be dropped"
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(239, DYN_MSG_FAC)) << X.RDB$FIELD_SOURCE <<
				QualifiedName(X.RDB$PROCEDURE_NAME,
					(X.RDB$PACKAGE_NAME.NULL ? NULL : X.RDB$PACKAGE_NAME)).toString().c_str() <<
				X.RDB$PARAMETER_NAME);
	}
	END_FOR

	//// FIXME: Check domain usage in functions.
}


//----------------------


void CreateAlterExceptionNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateAlterExceptionNode\n"
		"  name: '%s'  create: %d  alter: %d\n"
		"  message: '%s'\n",
		name.c_str(), create, alter, message.c_str());
}

void CreateAlterExceptionNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	fb_assert(create || alter);

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	if (alter)
	{
		if (!executeAlter(tdbb, transaction))
		{
			if (create)	// create or alter
				executeCreate(tdbb, transaction);
			else
			{
				// msg 144: "Exception not found"
				status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(144, DYN_MSG_FAC)));
			}
		}
	}
	else
		executeCreate(tdbb, transaction);

	savePoint.release();	// everything is ok
}

void CreateAlterExceptionNode::executeCreate(thread_db* tdbb, jrd_tra* transaction)
{
	executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_EXCEPTION, name);

	DYN_UTIL_check_unique_name(tdbb, transaction, name, obj_exception);

	AutoCacheRequest request(tdbb, drq_s_xcp, DYN_REQUESTS);
	int faults = 0;

	while (true)
	{
		try
		{
			SINT64 id = DYN_UTIL_gen_unique_id(tdbb, drq_g_nxt_xcp_id, "RDB$EXCEPTIONS");
			id %= (MAX_SSHORT + 1);

			if (!id)
				continue;

			STORE (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
				X IN RDB$EXCEPTIONS
			{
				X.RDB$EXCEPTION_NUMBER = id;
				X.RDB$SYSTEM_FLAG = 0;
				strcpy(X.RDB$EXCEPTION_NAME, name.c_str());

				fb_assert(message.length() < sizeof(X.RDB$MESSAGE));
				strcpy(X.RDB$MESSAGE, message.c_str());
			}
			END_STORE

			break;
		}
		catch (const status_exception& ex)
		{
			if (ex.value()[1] != isc_no_dup || ++faults > MAX_SSHORT)
				throw;

			fb_utils::init_status(tdbb->tdbb_status_vector);
		}
	}

	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_CREATE_EXCEPTION, name);
}

bool CreateAlterExceptionNode::executeAlter(thread_db* tdbb, jrd_tra* transaction)
{
	AutoCacheRequest request(tdbb, drq_m_xcp, DYN_REQUESTS);
	bool modified = false;

	FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$EXCEPTIONS
		WITH X.RDB$EXCEPTION_NAME EQ name.c_str()
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_EXCEPTION, name);

		MODIFY X
			fb_assert(message.length() < sizeof(X.RDB$MESSAGE));
			strcpy(X.RDB$MESSAGE, message.c_str());

			modified = true;
		END_MODIFY
	}
	END_FOR

	if (modified)
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_ALTER_EXCEPTION, name);

	return modified;
}


//----------------------


void DropExceptionNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropExceptionNode\n"
		"  name: '%s'\n",
		name.c_str());
}

void DropExceptionNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	AutoCacheRequest request(tdbb, drq_e_xcp, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$EXCEPTIONS
	    WITH X.RDB$EXCEPTION_NAME EQ name.c_str()
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_DROP_EXCEPTION, name);
		ERASE X;
		found = true;
	}
	END_FOR

	if (found)
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_DROP_EXCEPTION, name);
	else if (!silent)
	{
		// msg 144: "Exception not found"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(144, DYN_MSG_FAC)));
	}

	savePoint.release();	// everything is ok
}


//----------------------


void RecreateExceptionNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf("RecreateExceptionNode\n");
}

DdlNode* RecreateExceptionNode::internalDsqlPass()
{
	createNode->dsqlPass(dsqlScratch);
	dropNode.dsqlPass(dsqlScratch);
	return DdlNode::internalDsqlPass();
}

void RecreateExceptionNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	dropNode.execute(tdbb, transaction);
	createNode->execute(tdbb, transaction);

	savePoint.release();	// everything is ok
}


//----------------------


void CreateSequenceNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateSequenceNode\n"
		"  name: %s\n",
		name.c_str());
}

void CreateSequenceNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_SEQUENCE, name);
	store(tdbb, transaction, name, fb_sysflag_user);
	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_CREATE_SEQUENCE, name);
}

void CreateSequenceNode::store(thread_db* tdbb, jrd_tra* transaction, const MetaName& name,
	fb_sysflag sysFlag)
{
	DYN_UTIL_check_unique_name(tdbb, transaction, name, obj_generator);

	AutoCacheRequest request(tdbb, drq_s_gens, DYN_REQUESTS);
	int faults = 0;

	while (true)
	{
		try
		{
			SINT64 id = DYN_UTIL_gen_unique_id(tdbb, drq_g_nxt_gen_id, "RDB$GENERATORS");

			id %= MAX_SSHORT + 1;
			if (id == 0)
				continue;

			STORE (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
				X IN RDB$GENERATORS
			{
				X.RDB$GENERATOR_ID = id;
				X.RDB$SYSTEM_FLAG = (SSHORT) sysFlag;
				strcpy(X.RDB$GENERATOR_NAME, name.c_str());
			}
			END_STORE

			break;
		}
		catch (const status_exception& ex)
		{
			if (ex.value()[1] != isc_no_dup || ++faults > MAX_SSHORT)
				throw;

			fb_utils::init_status(tdbb->tdbb_status_vector);
		}
	}
}


//----------------------


// Delete a record from RDB$GENERATORS. Return true if succeeded.
bool DropSequenceNode::deleteGenerator(thread_db* tdbb, jrd_tra* transaction, const MetaName& name)
{
	AutoCacheRequest request(tdbb, drq_e_ident_gens, DYN_REQUESTS);
	bool found = false;

	FOR (REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		GEN IN RDB$GENERATORS
		WITH GEN.RDB$GENERATOR_NAME EQ name.c_str()
	{
		ERASE GEN;
		found = true;
	}
	END_FOR

	return found;
}


//----------------------


// Delete local field.
//
//  The rules for dropping a regular column:
//
//   1. the column is not referenced in any views.
//   2. the column is not part of any user defined indexes.
//   3. the column is not used in any SQL statements inside of store
//        procedures or triggers
//   4. the column is not part of any check-constraints
//
// The rules for dropping a column that was created as primary key:
//
//   1. the column is not defined as any foreign keys
//   2. the column is not defined as part of compound primary keys
//
// The rules for dropping a column that was created as foreign key:
//
//   1. the column is not defined as a compound foreign key. A
//        compound foreign key is a foreign key consisted of more
//        than one columns.
//
// The RI enforcement for dropping primary key column is done by system
// triggers and the RI enforcement for dropping foreign key column is
// done by code and system triggers. See the functional description of
// deleteKeyConstraint function for detail.
void RelationNode::deleteLocalField(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& relationName, const MetaName& fieldName)
{
	AutoCacheRequest request(tdbb, drq_l_dep_flds, DYN_REQUESTS);
	bool found = false;

	// Make sure that column is not referenced in any views.

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$RELATION_FIELDS CROSS
		Y IN RDB$RELATION_FIELDS CROSS
		Z IN RDB$VIEW_RELATIONS
		WITH X.RDB$RELATION_NAME EQ relationName.c_str() AND
			 X.RDB$FIELD_NAME EQ fieldName.c_str() AND
			 X.RDB$FIELD_NAME EQ Y.RDB$BASE_FIELD AND
			 X.RDB$FIELD_SOURCE EQ Y.RDB$FIELD_SOURCE AND
			 Y.RDB$RELATION_NAME EQ Z.RDB$VIEW_NAME AND
			 X.RDB$RELATION_NAME EQ Z.RDB$RELATION_NAME AND
			 Y.RDB$VIEW_CONTEXT EQ Z.RDB$VIEW_CONTEXT
	{
		// msg 52: "field %s from relation %s is referenced in view %s"
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(52, DYN_MSG_FAC)) <<
				fieldName << relationName << Y.RDB$RELATION_NAME);
	}
	END_FOR

	// If the column to be dropped is being used as a foreign key
	// and the column was not part of any compound foreign key,
	// then we can drop the column. But we have to drop the foreign key
	// constraint first.

	request.reset(tdbb, drq_g_rel_constr_nm, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDX IN RDB$INDICES CROSS
		IDX_SEG IN RDB$INDEX_SEGMENTS CROSS
		REL_CONST IN RDB$RELATION_CONSTRAINTS
		WITH IDX.RDB$RELATION_NAME EQ relationName.c_str() AND
			 REL_CONST.RDB$RELATION_NAME EQ relationName.c_str() AND
			 IDX_SEG.RDB$FIELD_NAME EQ fieldName.c_str() AND
			 IDX.RDB$INDEX_NAME EQ IDX_SEG.RDB$INDEX_NAME AND
			 IDX.RDB$INDEX_NAME EQ REL_CONST.RDB$INDEX_NAME AND
			 REL_CONST.RDB$CONSTRAINT_TYPE EQ FOREIGN_KEY
	{
		if (IDX.RDB$SEGMENT_COUNT == 1)
		{
			deleteKeyConstraint(tdbb, transaction, relationName,
				REL_CONST.RDB$CONSTRAINT_NAME, IDX.RDB$INDEX_NAME);
		}
		else
		{
			// msg 187: "field %s from relation %s is referenced in index %s"
			status_exception::raise(
				Arg::Gds(ENCODE_ISC_MSG(187, DYN_MSG_FAC)) <<
					fieldName << relationName << IDX.RDB$INDEX_NAME);
		}
	}
	END_FOR

	// Make sure that column is not referenced in any user-defined indexes.

	// NOTE: You still could see the system generated indices even though
	// they were already been deleted when dropping column that was used
	// as foreign key before "commit".

	request.reset(tdbb, drq_e_l_idx, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDX IN RDB$INDICES CROSS
		IDX_SEG IN RDB$INDEX_SEGMENTS
		WITH IDX.RDB$INDEX_NAME EQ IDX_SEG.RDB$INDEX_NAME AND
			 IDX.RDB$RELATION_NAME EQ relationName.c_str() AND
			 IDX_SEG.RDB$FIELD_NAME EQ fieldName.c_str() AND
			 NOT ANY REL_CONST IN RDB$RELATION_CONSTRAINTS
				WITH REL_CONST.RDB$RELATION_NAME EQ IDX.RDB$RELATION_NAME AND
					 REL_CONST.RDB$INDEX_NAME EQ IDX.RDB$INDEX_NAME
	{
		// msg 187: "field %s from relation %s is referenced in index %s"
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(187, DYN_MSG_FAC)) <<
				fieldName << relationName <<
				fb_utils::exact_name_limit(IDX.RDB$INDEX_NAME, sizeof(IDX.RDB$INDEX_NAME)));
	}
	END_FOR

	request.reset(tdbb, drq_e_lfield, DYN_REQUESTS);

	found = false;
	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		RFR IN RDB$RELATION_FIELDS
		WITH RFR.RDB$FIELD_NAME EQ fieldName.c_str() AND
			 RFR.RDB$RELATION_NAME EQ relationName.c_str()
	{
		if (!RFR.RDB$GENERATOR_NAME.NULL)
			DropSequenceNode::deleteGenerator(tdbb, transaction, RFR.RDB$GENERATOR_NAME);

		ERASE RFR;

		if (!RFR.RDB$SECURITY_CLASS.NULL &&
			!strncmp(RFR.RDB$SECURITY_CLASS, SQL_SECCLASS_PREFIX, SQL_SECCLASS_PREFIX_LEN))
		{
			deleteSecurityClass(tdbb, transaction, RFR.RDB$SECURITY_CLASS);
		}

		found = true;
		DropRelationNode::deleteGlobalField(tdbb, transaction, RFR.RDB$FIELD_SOURCE);
	}
	END_FOR

	request.reset(tdbb, drq_e_fld_prvs, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		PRIV IN RDB$USER_PRIVILEGES
		WITH PRIV.RDB$RELATION_NAME EQ relationName.c_str() AND
			 PRIV.RDB$FIELD_NAME EQ fieldName.c_str() AND
		     PRIV.RDB$OBJECT_TYPE = obj_relation
	{
		ERASE PRIV;
	}
	END_FOR

	if (!found)
	{
		// msg 176: "column %s does not exist in table/view %s"
		status_exception::raise(
			Arg::Gds(ENCODE_ISC_MSG(176, DYN_MSG_FAC)) << fieldName << relationName);
	}
}

void RelationNode::defineField(thread_db* tdbb, jrd_tra* transaction, const dsql_nod* element,
	SSHORT position, const dsql_nod* pkCols)
{
	Attachment* attachment = transaction->tra_attachment;
	dsql_fld* field = (dsql_fld*) element->nod_arg[Dsql::e_dfl_field];

	// Add the field to the relation being defined for parsing purposes.

	bool permanent = false;
	dsql_rel* relation = dsqlScratch->relation;
	if (relation != NULL)
	{
		if (!(relation->rel_flags & REL_new_relation))
		{
			dsql_fld* permField = FB_NEW(dsqlScratch->getAttachment()->dbb_pool) dsql_fld(
				dsqlScratch->getAttachment()->dbb_pool);

			*permField = *field;
			field = permField;
			permanent = true;
		}

		field->fld_next = relation->rel_fields;
		relation->rel_fields = field;
	}

	try
	{
		// Check for constraints.
		ObjectsArray<Constraint> constraints;
		bool notNullFlag = false;

		if (element->nod_arg[Dsql::e_dfl_identity])
			notNullFlag = true;	// identity columns are implicitly not null

		if (element->nod_arg[Dsql::e_dfl_constraint])
		{
			const dsql_nod* node = element->nod_arg[Dsql::e_dfl_constraint];
			const dsql_nod* const* const endPtr = node->nod_arg + node->nod_count;

			for (const dsql_nod* const* ptr = node->nod_arg; ptr != endPtr; ++ptr)
			{
				if ((*ptr)->nod_type == Dsql::nod_rel_constraint)
					makeConstraint(tdbb, transaction, *ptr, constraints, &notNullFlag);
			}
		}

		if (!notNullFlag && pkCols)
		{
			// Let's see if the field appears in a "primary_key (a, b, c)" relation constraint.
			for (int i = 0; !notNullFlag && i < pkCols->nod_count; ++i)
			{
				const dsql_str* pkFieldName = (dsql_str*) pkCols->nod_arg[i]->nod_arg[Dsql::e_fln_name];

				if (field->fld_name == pkFieldName->str_data)
					notNullFlag = true;
			}
		}

		AutoCacheRequest request(tdbb, drq_s_lfields2, DYN_REQUESTS);

		STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			RFR IN RDB$RELATION_FIELDS
		{
			const dsql_nod* domainNode = element->nod_arg[Dsql::e_dfl_domain];
			MetaName fieldSource;

			if (domainNode)
			{
				const dsql_nod* node1 = domainNode->nod_arg[Dsql::e_dom_name];
				const dsql_str* domainName = (dsql_str*) node1->nod_arg[Dsql::e_fln_name];

				// Get the domain information.
				if (!METD_get_domain(transaction, field, domainName->str_data))
				{
					// Specified domain or source field does not exist
					status_exception::raise(
						Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
						Arg::Gds(isc_dsql_command_err) <<
						Arg::Gds(isc_dsql_domain_not_found) << domainName->str_data);
				}

				fieldSource = domainName->str_data;
			}
			else
			{
				string computedSource;
				BlrWriter::BlrData computedValue;

				if (element->nod_arg[e_dfl_computed])
				{
					field->fld_flags |= FLD_computed;

					defineComputed(tdbb, field, element->nod_arg[e_dfl_computed],
						computedSource, computedValue);
				}

				TypeClause fieldType(field, NULL);	// Don't use the collate in the generated domain.
				fieldType.resolve(dsqlScratch);

				// Generate a domain.
				storeGlobalField(tdbb, transaction, fieldSource, fieldType,
					computedSource, computedValue);
			}

			if ((relation->rel_flags & REL_external) &&
				(field->fld_dtype == dtype_blob || field->fld_dtype == dtype_array ||
				 field->fld_dimensions))
			{
				const char* typeName = (field->fld_dtype == dtype_blob ? "BLOB" : "ARRAY");

				status_exception::raise(
					Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
					Arg::Gds(isc_dsql_command_err) <<
					Arg::Gds(isc_dsql_type_not_supp_ext_tab) << typeName << name << field->fld_name);
			}

			strcpy(RFR.RDB$FIELD_NAME, field->fld_name.c_str());
			strcpy(RFR.RDB$FIELD_SOURCE, fieldSource.c_str());
			strcpy(RFR.RDB$RELATION_NAME, name.c_str());
			RFR.RDB$SYSTEM_FLAG = 0;

			RFR.RDB$NULL_FLAG.NULL = TRUE;
			RFR.RDB$BASE_FIELD.NULL = TRUE;
			RFR.RDB$UPDATE_FLAG.NULL = TRUE;
			RFR.RDB$FIELD_POSITION.NULL = TRUE;
			RFR.RDB$VIEW_CONTEXT.NULL = TRUE;
			RFR.RDB$DEFAULT_VALUE.NULL = TRUE;
			RFR.RDB$DEFAULT_SOURCE.NULL = TRUE;
			RFR.RDB$COLLATION_ID.NULL = TRUE;
			RFR.RDB$GENERATOR_NAME.NULL = TRUE;
			RFR.RDB$IDENTITY_TYPE.NULL = TRUE;

			if (element->nod_arg[Dsql::e_dfl_collate])
			{
				DDL_resolve_intl_type(dsqlScratch, field, (dsql_str*) element->nod_arg[Dsql::e_dfl_collate]);

				RFR.RDB$COLLATION_ID.NULL = FALSE;
				RFR.RDB$COLLATION_ID = SSHORT(field->fld_collation_id);
			}

			if (element->nod_arg[Dsql::e_dfl_identity])
			{
				dsc desc;
				MET_get_domain(tdbb, fieldSource, &desc, NULL);

				if (!desc.isExact() || desc.dsc_scale != 0)
				{
					// Identity column @1 of table @2 must be exact numeric with zero scale.
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(273, DYN_MSG_FAC)) << field->fld_name << name);
				}

				MetaName sequenceName;
				DYN_UTIL_generate_generator_name(tdbb, sequenceName);

				CreateSequenceNode::store(tdbb, transaction, sequenceName,
					fb_sysflag_identity_generator);

				RFR.RDB$GENERATOR_NAME.NULL = FALSE;
				strcpy(RFR.RDB$GENERATOR_NAME, sequenceName.c_str());

				RFR.RDB$IDENTITY_TYPE.NULL = FALSE;
				RFR.RDB$IDENTITY_TYPE = IDENT_TYPE_BY_DEFAULT;
			}

			if (notNullFlag)
			{
				RFR.RDB$NULL_FLAG.NULL = FALSE;
				RFR.RDB$NULL_FLAG = TRUE;
			}

			if (element->nod_arg[Dsql::e_dfl_default])
			{
				string defaultSource;
				BlrWriter::BlrData defaultValue;

				if (defineDefault(tdbb, field, element->nod_arg[Dsql::e_dfl_default], defaultSource,
						defaultValue) &&
					notNullFlag)
				{
					status_exception::raise(
						Arg::Gds(isc_sqlerr) << Arg::Num(-204) <<
						Arg::Gds(isc_bad_default_value) <<
						Arg::Gds(isc_invalid_clause) << "default null not null");
				}

				RFR.RDB$DEFAULT_SOURCE.NULL = FALSE;
				attachment->storeMetaDataBlob(tdbb, transaction, &RFR.RDB$DEFAULT_SOURCE, defaultSource);

				RFR.RDB$DEFAULT_VALUE.NULL = FALSE;
				attachment->storeBinaryBlob(tdbb, transaction, &RFR.RDB$DEFAULT_VALUE, defaultValue);
			}

			if (position == -1)
			{
				SLONG fieldPos = -1;
				DYN_UTIL_generate_field_position(tdbb, NULL, name, &fieldPos);
				if (fieldPos >= 0)
					position = SSHORT(fieldPos + 1);
			}

			if (position >= 0)
			{
				RFR.RDB$FIELD_POSITION.NULL = FALSE;
				RFR.RDB$FIELD_POSITION = position;
			}
		}
		END_STORE

		// Define the field constraints.
		for (ObjectsArray<Constraint>::iterator constraint(constraints.begin());
			 constraint != constraints.end();
			 ++constraint)
		{
			if (constraint->type != Constraint::TYPE_FK)
				constraint->columns.add(field->fld_name);
			defineConstraint(tdbb, transaction, *constraint);
		}
	}
	catch (const Exception&)
	{
		clearPermanentField(relation, permanent);
		throw;
	}

	clearPermanentField(relation, permanent);
}

// Define a COMPUTED BY clause.
void RelationNode::defineComputed(thread_db* tdbb, dsql_fld* field, dsql_nod* node,
	string& source, BlrWriter::BlrData& value)
{
	AutoSetRestore2<dsql_nod*, DsqlCompiledStatement> autoDdlNode(dsqlScratch->getStatement(),
		&DsqlCompiledStatement::getDdlNode, &DsqlCompiledStatement::setDdlNode, node);

	// Get the table node and set up correct context.
	DDL_reset_context_stack(dsqlScratch);

	// Save the size of the field if it is specified.
	dsc saveDesc;
	saveDesc.dsc_dtype = 0;

	if (field && field->fld_dtype)
	{
		fb_assert(field->fld_dtype <= MAX_UCHAR);
		saveDesc.dsc_dtype = (UCHAR) field->fld_dtype;
		saveDesc.dsc_length = field->fld_length;
		fb_assert(field->fld_scale <= MAX_SCHAR);
		saveDesc.dsc_scale = (SCHAR) field->fld_scale;
		saveDesc.dsc_sub_type = field->fld_sub_type;

		field->fld_dtype = 0;
		field->fld_length = 0;
		field->fld_scale = 0;
		field->fld_sub_type = 0;
	}

	PASS1_make_context(dsqlScratch, dsqlNode);

	dsql_nod* input = PASS1_node(dsqlScratch, node->nod_arg[Dsql::e_cmp_expr]);

	// Try to calculate size of the computed field. The calculated size
	// may be ignored, but it will catch self references.
	dsc desc;
	MAKE_desc(dsqlScratch, &desc, input, NULL);

	// Generate the blr expression.

	dsqlScratch->getBlrData().clear();
	dsqlScratch->getDebugData().clear();
	dsqlScratch->appendUChar(dsqlScratch->isVersion4() ? blr_version4 : blr_version5);

	GEN_hidden_variables(dsqlScratch, true);
	GEN_expr(dsqlScratch, input);
	dsqlScratch->appendUChar(blr_eoc);

	if (saveDesc.dsc_dtype)
	{
		// Restore the field size/type overrides.
		field->fld_dtype = saveDesc.dsc_dtype;
		field->fld_length = saveDesc.dsc_length;
		field->fld_scale = saveDesc.dsc_scale;

		if (field->fld_dtype <= dtype_any_text)
		{
			field->fld_character_set_id = DSC_GET_CHARSET(&saveDesc);
			field->fld_collation_id= DSC_GET_COLLATE(&saveDesc);
		}
		else
			field->fld_sub_type = saveDesc.dsc_sub_type;
	}
	else if (field)
	{
		// Use size calculated.
		field->fld_dtype = desc.dsc_dtype;
		field->fld_length = desc.dsc_length;
		field->fld_scale = desc.dsc_scale;

		if (field->fld_dtype <= dtype_any_text)
		{
			field->fld_character_set_id = DSC_GET_CHARSET(&desc);
			field->fld_collation_id= DSC_GET_COLLATE(&desc);
		}
		else
			field->fld_sub_type = desc.dsc_sub_type;
	}

	DDL_reset_context_stack(dsqlScratch);

	// Generate the source text.
	const dsql_str* sourceStr = (dsql_str*) node->nod_arg[Dsql::e_cmp_text];
	fb_assert(sourceStr->str_length <= MAX_USHORT);
	source = string(sourceStr->str_data, sourceStr->str_length);

	value.assign(dsqlScratch->getBlrData());
}

// Define a DEFAULT clause. Return true for DEFAULT NULL.
bool RelationNode::defineDefault(thread_db* tdbb, dsql_fld* field, dsql_nod* node,
	string& source, BlrWriter::BlrData& value)
{
	dsql_nod* input = PASS1_node(dsqlScratch, node->nod_arg[Dsql::e_dft_default]);

	// Generate the blr expression.

	dsqlScratch->getBlrData().clear();
	dsqlScratch->getDebugData().clear();
	dsqlScratch->appendUChar(dsqlScratch->isVersion4() ? blr_version4 : blr_version5);

	GEN_hidden_variables(dsqlScratch, true);
	GEN_expr(dsqlScratch, input);
	dsqlScratch->appendUChar(blr_eoc);

	// Generate the source text.
	const dsql_str* sourceStr = (dsql_str*) node->nod_arg[Dsql::e_dft_default_source];
	fb_assert(sourceStr->str_length <= MAX_USHORT);
	source = string(sourceStr->str_data, sourceStr->str_length);

	value.assign(dsqlScratch->getBlrData());

	return input->nod_type == Dsql::nod_null;
}

// Make a constraint object from a legacy node.
void RelationNode::makeConstraint(thread_db* tdbb, jrd_tra* transaction, const dsql_nod* node,
	ObjectsArray<Constraint>& constraints, bool* notNull)
{
	const dsql_str* string = (dsql_str*) node->nod_arg[Dsql::e_rct_name];
	dsql_nod* constraintNode = node->nod_arg[Dsql::e_rct_type];

	switch (constraintNode->nod_type)
	{
		case Dsql::nod_null:
		case Dsql::nod_primary:
			if (notNull && !*notNull)
			{
				*notNull = true;

				Constraint& constraint = constraints.add();
				constraint.type = Constraint::TYPE_NOT_NULL;
				if (string && constraintNode->nod_type == Dsql::nod_null)
					constraint.name = string->str_data;
			}

			if (constraintNode->nod_type == Dsql::nod_null)
				break;
			// nod_primary falls into

		case Dsql::nod_unique:
		{
			Constraint& constraint = constraints.add();
			constraint.type = constraintNode->nod_type == Dsql::nod_primary ?
				Constraint::TYPE_PK : Constraint::TYPE_UNIQUE;
			if (string)
				constraint.name = string->str_data;

			const dsql_nod* index = constraintNode->nod_arg[Dsql::e_pri_index];
			fb_assert(index);

			string = (dsql_str*) index->nod_arg[Dsql::e_idx_name];
			constraint.indexName = (string ? string->str_data : constraint.name.c_str());

			if (index->nod_arg[Dsql::e_idx_asc_dsc])
				constraint.descending = true;

			const dsql_nod* columns = constraintNode->nod_arg[Dsql::e_pri_columns];
			if (columns)
			{
				const dsql_nod* const* ptr = columns->nod_arg;

				for (const dsql_nod* const* const end = ptr + columns->nod_count; ptr < end; ++ptr)
				{
					const dsql_str* fieldName = (dsql_str*) (*ptr)->nod_arg[Dsql::e_fln_name];
					constraint.columns.add(fieldName->str_data);
				}
			}

			break;
		}

		case Dsql::nod_foreign:
		{
			Constraint& constraint = constraints.add();
			constraint.type = Constraint::TYPE_FK;
			if (string)
				constraint.name = string->str_data;

			dsql_nod* columns = constraintNode->nod_arg[Dsql::e_for_columns];
			dsql_nod* refRelationNode = constraintNode->nod_arg[Dsql::e_for_reftable];

			const dsql_str* refRelation = (dsql_str*) refRelationNode->nod_arg[Dsql::e_rln_name];
			constraint.refRelation = refRelation->str_data;

			// If there is a referenced table name but no referenced field names, the
			// primary key of the referenced table designates the referenced fields.
			dsql_nod* refColumns = constraintNode->nod_arg[Dsql::e_for_refcolumns];
			if (!refColumns)
			{
				refColumns = METD_get_primary_key(transaction, refRelation);

				// If there is NEITHER an explicitly referenced field name, NOR does
				// the referenced table have a primary key to serve as the implicitly
				// referenced field, fail.
				if (!refColumns)
				{
					// "REFERENCES table" without "(column)" requires PRIMARY
					// KEY on referenced table

					status_exception::raise(
						Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
						Arg::Gds(isc_dsql_command_err) <<
						Arg::Gds(isc_reftable_requires_pk));
				}
			}

			if (refColumns && columns->nod_count != refColumns->nod_count)
			{
				// Foreign key field count does not match primary key.
				status_exception::raise(
					Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
					Arg::Gds(isc_dsql_command_err) <<
					Arg::Gds(isc_key_field_count_err));
			}

			// Define the foreign key index and the triggers that may be needed
			// for referential integrity action.

			const dsql_nod* index = constraintNode->nod_arg[Dsql::e_for_index];
			fb_assert(index);

			string = (dsql_str*) index->nod_arg[Dsql::e_idx_name];
			constraint.indexName = (string ? string->str_data : constraint.name.c_str());

			if (index->nod_arg[Dsql::e_idx_asc_dsc])
				constraint.descending = true;

			if (columns)
			{
				const dsql_nod* const* ptr = columns->nod_arg;

				for (const dsql_nod* const* const end = ptr + columns->nod_count; ptr < end; ++ptr)
				{
					const dsql_str* fieldName = (dsql_str*) (*ptr)->nod_arg[Dsql::e_fln_name];
					constraint.columns.add(fieldName->str_data);
				}
			}

			if (refColumns)
			{
				const dsql_nod* const* ptr = refColumns->nod_arg;

				for (const dsql_nod* const* const end = ptr + refColumns->nod_count; ptr < end; ++ptr)
				{
					const dsql_str* fieldName = (dsql_str*) (*ptr)->nod_arg[Dsql::e_fln_name];
					constraint.refColumns.add(fieldName->str_data);
				}
			}

			if (constraintNode->nod_arg[Dsql::e_for_action])
			{
				dsql_nod* forActionNode = constraintNode->nod_arg[Dsql::e_for_action];
				fb_assert(forActionNode->nod_type == Dsql::nod_ref_upd_del);

				dsql_nod* refUpdActionNode = forActionNode->nod_arg[Dsql::e_ref_upd];
				if (refUpdActionNode)
				{
					fb_assert(refUpdActionNode->nod_type == Dsql::nod_ref_trig_action);

					switch (refUpdActionNode->nod_flags)
					{
						case REF_ACTION_CASCADE:
							constraint.refUpdateAction = RI_ACTION_CASCADE;
							defineUpdateCascadeTrigger(constraint);
							break;

						case REF_ACTION_SET_DEFAULT:
							constraint.refUpdateAction = RI_ACTION_DEFAULT;
							defineSetDefaultTrigger(constraint, true);
							break;

						case REF_ACTION_SET_NULL:
							constraint.refUpdateAction = RI_ACTION_NULL;
							defineSetNullTrigger(constraint, true);
							break;

						default:
							fb_assert(0);
							// fall into

						case REF_ACTION_NONE:
							constraint.refUpdateAction = RI_ACTION_NONE;
							break;
					}
				}

				dsql_nod* refDelActionNode = forActionNode->nod_arg[Dsql::e_ref_del];
				if (refDelActionNode)
				{
					fb_assert(refDelActionNode->nod_type == Dsql::nod_ref_trig_action);

					switch (refDelActionNode->nod_flags)
					{
						case REF_ACTION_CASCADE:
							constraint.refDeleteAction = RI_ACTION_CASCADE;
							defineDeleteCascadeTrigger(constraint);
							break;

						case REF_ACTION_SET_DEFAULT:
							constraint.refDeleteAction = RI_ACTION_DEFAULT;
							defineSetDefaultTrigger(constraint, false);
							break;

						case REF_ACTION_SET_NULL:
							constraint.refDeleteAction = RI_ACTION_NULL;
							defineSetNullTrigger(constraint, false);
							break;

						default:
							fb_assert(0);
							// fall into

						case REF_ACTION_NONE:
							constraint.refDeleteAction = RI_ACTION_NONE;
							break;
					}
				}
			}

			break;
		}

		case Dsql::nod_def_constraint:
		{
			Constraint& constraint = constraints.add();
			constraint.type = Constraint::TYPE_CHECK;
			if (string)
				constraint.name = string->str_data;

			defineCheckConstraint(constraint, constraintNode);
			break;
		}
	}
}

// Define a constraint.
void RelationNode::defineConstraint(thread_db* tdbb, jrd_tra* transaction, Constraint& constraint)
{
	if (constraint.name.isEmpty())
		DYN_UTIL_generate_constraint_name(tdbb, NULL, constraint.name);

	AutoCacheRequest request(tdbb, drq_s_rel_con, DYN_REQUESTS);
	MetaName referredIndexName;

	STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		CRT IN RDB$RELATION_CONSTRAINTS
	{
		CRT.RDB$INDEX_NAME.NULL = TRUE;

		strcpy(CRT.RDB$CONSTRAINT_NAME, constraint.name.c_str());
		strcpy(CRT.RDB$RELATION_NAME, name.c_str());

		switch (constraint.type)
		{
			case Constraint::TYPE_CHECK:
				strcpy(CRT.RDB$CONSTRAINT_TYPE, CHECK_CNSTRT);
				break;

			case Constraint::TYPE_NOT_NULL:
				strcpy(CRT.RDB$CONSTRAINT_TYPE, NOT_NULL_CNSTRT);
				break;

			case Constraint::TYPE_PK:
				strcpy(CRT.RDB$CONSTRAINT_TYPE, PRIMARY_KEY);
				break;

			case Constraint::TYPE_UNIQUE:
				strcpy(CRT.RDB$CONSTRAINT_TYPE, UNIQUE_CNSTRT);
				break;

			case Constraint::TYPE_FK:
				strcpy(CRT.RDB$CONSTRAINT_TYPE, FOREIGN_KEY);
				break;

			default:
				fb_assert(false);
		}

		// These constraints requires creation of an index.
		switch (constraint.type)
		{
			case Constraint::TYPE_PK:
			case Constraint::TYPE_UNIQUE:
			case Constraint::TYPE_FK:
			{
				CreateIndexNode::Definition definition;
				definition.relation = name;
				definition.type = (constraint.type == Constraint::TYPE_PK ?
					isc_dyn_def_primary_key :
					(constraint.type == Constraint::TYPE_FK ? isc_dyn_def_foreign_key : 0));
				definition.unique = constraint.type != Constraint::TYPE_FK;
				if (constraint.descending)
					definition.descending = true;
				definition.columns = constraint.columns;
				definition.refRelation = constraint.refRelation;
				definition.refColumns = constraint.refColumns;

				CreateIndexNode::store(tdbb, transaction, constraint.indexName, definition,
					&referredIndexName);

				CRT.RDB$INDEX_NAME.NULL = FALSE;
				strcpy(CRT.RDB$INDEX_NAME, constraint.indexName.c_str());

				checkForeignKeyTempScope(tdbb, transaction, name, referredIndexName);

				// Check that we have references permissions on the table and
				// fields that the index:referredIndexName is on.
				SCL_check_index(tdbb, referredIndexName, 0, SCL_sql_references);

				break;
			}
		}
	}
	END_STORE

	if (constraint.type == Constraint::TYPE_NOT_NULL)
	{
		fb_assert(constraint.columns.getCount() == 1);
		DYN_UTIL_store_check_constraints(tdbb, transaction, constraint.name,
			*constraint.columns.begin());
	}

	// Define the automatically generated triggers.

	for (ObjectsArray<TriggerDefinition>::iterator trigger(constraint.triggers.begin());
		 trigger != constraint.triggers.end();
		 ++trigger)
	{
		trigger->store(tdbb, transaction);
		DYN_UTIL_store_check_constraints(tdbb, transaction, constraint.name, trigger->name);
	}

	if (constraint.type == Constraint::TYPE_NOT_NULL || constraint.type == Constraint::TYPE_CHECK)
		return;

	// Make sure unique field names were specified for UNIQUE/PRIMARY/FOREIGN
	// All fields must have the NOT NULL attribute specified for UNIQUE/PRIMARY.

	request.reset(tdbb, drq_c_unq_nam2, DYN_REQUESTS);

	int allCount = 0;
	int uniqueCount = 0;
	ObjectsArray<MetaName> fieldList;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDS IN RDB$INDEX_SEGMENTS CROSS
		RFR IN RDB$RELATION_FIELDS CROSS
		FLX IN RDB$FIELDS
		WITH IDS.RDB$INDEX_NAME EQ constraint.indexName.c_str() AND
			 RFR.RDB$RELATION_NAME EQ name.c_str() AND
			 RFR.RDB$FIELD_NAME EQ IDS.RDB$FIELD_NAME AND
			 FLX.RDB$FIELD_NAME EQ RFR.RDB$FIELD_SOURCE
		REDUCED TO IDS.RDB$FIELD_NAME, IDS.RDB$INDEX_NAME, FLX.RDB$NULL_FLAG
		SORTED BY ASCENDING IDS.RDB$FIELD_NAME
	{
		if ((FLX.RDB$NULL_FLAG.NULL || !FLX.RDB$NULL_FLAG) &&
			(RFR.RDB$NULL_FLAG.NULL || !RFR.RDB$NULL_FLAG) &&
			constraint.type == Constraint::TYPE_PK)
		{
			// msg 123: "Field: %s not defined as NOT NULL - can't be used in PRIMARY KEY
			// constraint definition"
			status_exception::raise(
				Arg::Gds(ENCODE_ISC_MSG(123, DYN_MSG_FAC)) << MetaName(RFR.RDB$FIELD_NAME));
		}

		++uniqueCount;
		fieldList.add() = IDS.RDB$FIELD_NAME;
	}
	END_FOR

	request.reset(tdbb, drq_n_idx_seg, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDS IN RDB$INDEX_SEGMENTS
		WITH IDS.RDB$INDEX_NAME EQ constraint.indexName.c_str()
	{
		++allCount;
	}
	END_FOR

	if (uniqueCount != allCount)
	{
		// msg 124: "A column name is repeated in the definition of constraint: %s"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(124, DYN_MSG_FAC)) << constraint.name);
	}

	if (constraint.type == Constraint::TYPE_FK)
	{
		request.reset(tdbb, drq_s_ref_con, DYN_REQUESTS);

		STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			REF IN RDB$REF_CONSTRAINTS
		{
			AutoCacheRequest request2(tdbb, drq_l_intg_con, DYN_REQUESTS);

			FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
				CRT IN RDB$RELATION_CONSTRAINTS
				WITH CRT.RDB$INDEX_NAME EQ referredIndexName.c_str() AND
					 (CRT.RDB$CONSTRAINT_TYPE = PRIMARY_KEY OR
					  CRT.RDB$CONSTRAINT_TYPE = UNIQUE_CNSTRT)
			{
				fb_utils::exact_name_limit(CRT.RDB$CONSTRAINT_NAME, sizeof(CRT.RDB$CONSTRAINT_NAME));
				strcpy(REF.RDB$CONST_NAME_UQ, CRT.RDB$CONSTRAINT_NAME);
				strcpy(REF.RDB$CONSTRAINT_NAME, constraint.name.c_str());

				REF.RDB$UPDATE_RULE.NULL = FALSE;
				strcpy(REF.RDB$UPDATE_RULE, constraint.refUpdateAction);

				REF.RDB$DELETE_RULE.NULL = FALSE;
				strcpy(REF.RDB$DELETE_RULE, constraint.refDeleteAction);
			}
			END_FOR
		}
		END_STORE
	}
	else
	{
		// For PRIMARY KEY/UNIQUE constraints, make sure same set of columns
		// is not used in another constraint of either type.

		request.reset(tdbb, drq_c_dup_con, DYN_REQUESTS);

		MetaName indexName;
		int listIndex = -1;
		bool found = false;

		FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			CRT IN RDB$RELATION_CONSTRAINTS CROSS
			IDS IN RDB$INDEX_SEGMENTS OVER RDB$INDEX_NAME
			WITH CRT.RDB$RELATION_NAME EQ name.c_str() AND
				 CRT.RDB$CONSTRAINT_NAME NE constraint.name.c_str() AND
				 (CRT.RDB$CONSTRAINT_TYPE EQ PRIMARY_KEY OR
				  CRT.RDB$CONSTRAINT_TYPE EQ UNIQUE_CNSTRT)
			SORTED BY CRT.RDB$INDEX_NAME, DESCENDING IDS.RDB$FIELD_NAME
		{
			if (indexName != CRT.RDB$INDEX_NAME)
			{
				if (listIndex >= 0)
					found = false;

				if (found)
					break;

				listIndex = fieldList.getCount() - 1;
				indexName = CRT.RDB$INDEX_NAME;
				found = true;
			}

			if (listIndex >= 0)
			{
				if (fieldList[listIndex--] != IDS.RDB$FIELD_NAME)
					found = false;
			}
			else
				found = false;
		}
		END_FOR

		if (listIndex >= 0)
			found = false;

		if (found)
		{
			// msg 126: "Same set of columns cannot be used in more than one PRIMARY KEY
			// and/or UNIQUE constraint definition"
			status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(126, DYN_MSG_FAC)));
		}
	}
}

// Generate triggers to implement the CHECK clause, either at the field or table level.
void RelationNode::defineCheckConstraint(Constraint& constraint, dsql_nod* node)
{
	defineCheckConstraintTrigger(constraint, node, PRE_STORE_TRIGGER);	// Create the INSERT trigger.
	defineCheckConstraintTrigger(constraint, node, PRE_MODIFY_TRIGGER);	// Create the UPDATE trigger.
}

// Define a check constraint trigger.
void RelationNode::defineCheckConstraintTrigger(Constraint& constraint, dsql_nod* node,
	FB_UINT64 triggerType)
{
	// See hack at pass1_field.
	AutoSetRestore2<dsql_nod*, DsqlCompiledStatement> autoDdlNode(dsqlScratch->getStatement(),
		&DsqlCompiledStatement::getDdlNode, &DsqlCompiledStatement::setDdlNode, node);

	Constraint::BlrWriter& blrWriter = constraint.blrWritersHolder.add();
	blrWriter.init(dsqlScratch);

	// Specify that the trigger should abort if the condition is not met.
	dsql_nod* actionNode = MAKE_node(Dsql::nod_list, 1);
	actionNode->nod_arg[0] = MAKE_node(Dsql::nod_gdscode, 1);
	actionNode->nod_arg[0]->nod_arg[0] = (dsql_nod*) MAKE_cstring("check_constraint");

	// Generate the trigger blr.

	dsqlScratch->getBlrData().clear();
	dsqlScratch->getDebugData().clear();

	dsqlScratch->appendUChar(blr_begin);

	// Create the "OLD" and "NEW" contexts for the trigger -- the new one could be a dummy
	// place holder to avoid resolving fields to that context but prevent relations referenced
	// in the trigger actions from referencing the predefined "1" context.

	DDL_reset_context_stack(dsqlScratch);

	// CVC: I thought I could disable the OLD context here to avoid "ambiguous field name"
	// errors in pre_store and pre_modify triggers. Also, what sense can I make from NEW in
	// pre_delete? However, we clash at JRD with "no current record for fetch operation".

	dsqlNode->nod_arg[Dsql::e_rln_alias] = (dsql_nod*) MAKE_cstring(OLD_CONTEXT);
	dsql_ctx* oldContext = PASS1_make_context(dsqlScratch, dsqlNode);
	oldContext->ctx_flags |= CTX_system;

	dsqlNode->nod_arg[Dsql::e_rln_alias] = (dsql_nod*) MAKE_cstring(NEW_CONTEXT);
	dsql_ctx* newContext = PASS1_make_context(dsqlScratch, dsqlNode);
	newContext->ctx_flags |= CTX_system;

	// Generate the condition for firing the trigger.

	dsql_nod* condition = MAKE_node(Dsql::nod_not, 1);
	condition->nod_arg[0] = node->nod_arg[Dsql::e_cnstr_condition];
	condition = PASS1_node(dsqlScratch, condition);

	GEN_hidden_variables(dsqlScratch, false);
	dsqlScratch->appendUChar(blr_if);
	GEN_expr(dsqlScratch, condition);

	// Generate the action statement for the trigger.
	GEN_statement(dsqlScratch, PASS1_statement(dsqlScratch, actionNode));

	dsqlScratch->appendUChar(blr_end);	// of if (as there's no ELSE branch)
	dsqlScratch->appendUChar(blr_end);	// of begin

	dsqlScratch->appendUChar(blr_eoc);	// end of the blr

	DDL_reset_context_stack(dsqlScratch);

	// Move the blr to the constraint blrWriter.
	blrWriter.getBlrData().join(dsqlScratch->getBlrData());

	TriggerDefinition& trigger = constraint.triggers.add();
	trigger.systemFlag = fb_sysflag_check_constraint;
	trigger.relationName = name;
	trigger.type = triggerType;
	trigger.source = ((dsql_str*) node->nod_arg[Dsql::e_cnstr_source])->str_data;
	trigger.blrData = blrWriter.getBlrData();
}

// Define "on delete|update set default" trigger (for referential integrity) along with its blr.
void RelationNode::defineSetDefaultTrigger(Constraint& constraint, bool onUpdate)
{
	Constraint::BlrWriter& blrWriter = constraint.blrWritersHolder.add();
	blrWriter.init(dsqlScratch);

	generateUnnamedTriggerBeginning(constraint, onUpdate, blrWriter);

	const int BLOB_BUFFER_SIZE = 4096;	// to read in blr blob for default values
	UCHAR defaultVal[BLOB_BUFFER_SIZE];

	for (ObjectsArray<MetaName>::const_iterator column(constraint.columns.begin());
		 column != constraint.columns.end();
		 ++column)
	{
		blrWriter.appendUChar(blr_assignment);

		// ASF: This is wrong way to do the thing. See CORE-3073.

		// Here stuff the default value as blr_literal .... or blr_null
		// if this column does not have an applicable default.
		// The default is determined in many cases:
		// (1) the info. for the column is in memory. (This is because
		// the column is being created in this ddl statement).
		// (1-a) the table has a column level default. We get this by
		// searching the dsql parse tree.
		// (1-b) the table does not have a column level default, but
		// has a domain default. We get the domain name from the dsql
		// parse tree and call METD_get_domain_default to read the
		// default from the system tables.
		// (2) The default-info for this column is not in memory (This is
		// because this is an alter table ddl statement). The table
		// already exists; therefore we get the column and/or domain
		// default value from the system tables by calling:
		// METD_get_col_default().

		bool foundDefault = false;
		bool searchForDefault = true;

		// Search the parse tree to find the column

		for (const dsql_nod* const* ptr = elements.begin(); ptr != elements.end(); ++ptr)
		{
			const dsql_nod* elem = *ptr;

			if (elem->nod_type != Dsql::nod_def_field)
				continue;

			const dsql_fld* field = (dsql_fld*) elem->nod_arg[Dsql::e_dfl_field];
			if (*column != field->fld_name)
				continue;

			// Now we have the right column in the parse tree. case (1) above

			dsql_nod* default_node = elem->nod_arg[Dsql::e_dfl_default];
			if (default_node)
			{
				// case (1-a) above: There is a column level default
				fb_assert(default_node->nod_type == Dsql::nod_def_default);

				dsqlScratch->getBlrData().clear();
				dsqlScratch->getDebugData().clear();

				GEN_hidden_variables(dsqlScratch, true);
				GEN_expr(dsqlScratch, default_node->nod_arg[Dsql::e_dft_default]);

				foundDefault = true;
				searchForDefault = false;

				// Move the blr to the constraint blrWriter.
				blrWriter.getBlrData().join(dsqlScratch->getBlrData());
			}
			else
			{
				const TEXT* domainName;
				const dsql_str* domainNameStr;
				const dsql_nod* tmpNode;

				const dsql_nod* domainNode = elem->nod_arg[Dsql::e_dfl_domain];
				if (!domainNode ||
					!(tmpNode = domainNode->nod_arg[Dsql::e_dom_name]) ||
					!(domainNameStr = (dsql_str*) tmpNode->nod_arg[Dsql::e_fln_name]) ||
					!(domainName = domainNameStr->str_data))
				{
					break;
				}

				// case: (1-b): Domain name is available. Column level default
				// is not declared. So get the domain default.
				const USHORT defaultLen = METD_get_domain_default(dsqlScratch->getTransaction(),
					domainName, &foundDefault, defaultVal, sizeof(defaultVal));

				searchForDefault = false;

				if (foundDefault)
					stuffDefaultBlr(ByteChunk(defaultVal, defaultLen), blrWriter);
				else
				{
					// Neither column level nor domain level default exists.
					blrWriter.appendUChar(blr_null);
				}
			}

			break;
		}

		if (searchForDefault)
		{
			// case 2: See if the column/domain has already been created.

			const USHORT defaultLen = METD_get_col_default(dsqlScratch->getTransaction(),
				name.c_str(), column->c_str(), &foundDefault, defaultVal, sizeof(defaultVal));

			if (foundDefault)
				stuffDefaultBlr(ByteChunk(defaultVal, defaultLen), blrWriter);
			else
				blrWriter.appendUChar(blr_null);
		}

		// The context for the foreign key relation.
		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(2);
		blrWriter.appendNullString(0, column->c_str());
	}

	blrWriter.appendUChar(blr_end);

	if (onUpdate)
		blrWriter.appendUCharRepeated(blr_end, 3);

	blrWriter.appendUChar(blr_eoc);	// end of the blr

	TriggerDefinition& trigger = constraint.triggers.add();
	trigger.systemFlag = fb_sysflag_referential_constraint;
	trigger.fkTrigger = true;
	trigger.relationName = constraint.refRelation;
	trigger.type = (onUpdate ? POST_MODIFY_TRIGGER : POST_ERASE_TRIGGER);
	trigger.blrData = blrWriter.getBlrData();
}

// Define "on delete/update set null" trigger (for referential integrity).
// The trigger blr is the same for both the delete and update cases. Only difference is its
// TRIGGER_TYPE (ON DELETE or ON UPDATE).
// When onUpdate parameter == true is an update trigger.
void RelationNode::defineSetNullTrigger(Constraint& constraint, bool onUpdate)
{
	fb_assert(constraint.columns.getCount() == constraint.refColumns.getCount());
	fb_assert(constraint.columns.hasData());

	Constraint::BlrWriter& blrWriter = constraint.blrWritersHolder.add();
	blrWriter.init(dsqlScratch);

	generateUnnamedTriggerBeginning(constraint, onUpdate, blrWriter);

	for (ObjectsArray<MetaName>::const_iterator column(constraint.columns.begin());
		 column != constraint.columns.end();
		 ++column)
	{
		blrWriter.appendUChar(blr_assignment);
		blrWriter.appendUChar(blr_null);
		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(2);
		blrWriter.appendNullString(0, column->c_str());
	}

	blrWriter.appendUChar(blr_end);

	if (onUpdate)
		blrWriter.appendUCharRepeated(blr_end, 3);

	blrWriter.appendUChar(blr_eoc);	// end of the blr

	TriggerDefinition& trigger = constraint.triggers.add();
	trigger.systemFlag = fb_sysflag_referential_constraint;
	trigger.fkTrigger = true;
	trigger.relationName = constraint.refRelation;
	trigger.type = (onUpdate ? POST_MODIFY_TRIGGER : POST_ERASE_TRIGGER);
	trigger.blrData = blrWriter.getBlrData();
}

// Define "on delete cascade" trigger (for referential integrity) along with the trigger blr.
void RelationNode::defineDeleteCascadeTrigger(Constraint& constraint)
{
	fb_assert(constraint.columns.getCount() == constraint.refColumns.getCount());
	fb_assert(constraint.columns.hasData());

	Constraint::BlrWriter& blrWriter = constraint.blrWritersHolder.add();
	blrWriter.init(dsqlScratch);

	blrWriter.appendUChar(blr_for);
	blrWriter.appendUChar(blr_rse);

	// The context for the prim. key relation.
	blrWriter.appendUChar(1);
	blrWriter.appendUChar(blr_relation);
	blrWriter.appendNullString(0, name.c_str());
	// The context for the foreign key relation.
	blrWriter.appendUChar(2);

	// Generate the blr for: foreign_key == primary_key.
	stuffMatchingBlr(constraint, blrWriter);

	blrWriter.appendUChar(blr_erase);
	blrWriter.appendUChar(2);

	blrWriter.appendUChar(blr_eoc);	// end of the blr

	TriggerDefinition& trigger = constraint.triggers.add();
	trigger.systemFlag = fb_sysflag_referential_constraint;
	trigger.fkTrigger = true;
	trigger.relationName = constraint.refRelation;
	trigger.type = POST_ERASE_TRIGGER;
	trigger.blrData = blrWriter.getBlrData();
}

// Define "on update cascade" trigger (for referential integrity) along with the trigger blr.
void RelationNode::defineUpdateCascadeTrigger(Constraint& constraint)
{
	fb_assert(constraint.columns.getCount() == constraint.refColumns.getCount());
	fb_assert(constraint.columns.hasData());

	Constraint::BlrWriter& blrWriter = constraint.blrWritersHolder.add();
	blrWriter.init(dsqlScratch);

	generateUnnamedTriggerBeginning(constraint, true, blrWriter);

	for (ObjectsArray<MetaName>::const_iterator column(constraint.columns.begin()),
			refColumn(constraint.refColumns.begin());
		 column != constraint.columns.end();
		 ++column, ++refColumn)
	{
		blrWriter.appendUChar(blr_assignment);

		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(1);
		blrWriter.appendNullString(0, refColumn->c_str());

		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(2);
		blrWriter.appendNullString(0, column->c_str());
	}

	blrWriter.appendUCharRepeated(blr_end, 4);
	blrWriter.appendUChar(blr_eoc);	// end of the blr

	TriggerDefinition& trigger = constraint.triggers.add();
	trigger.systemFlag = fb_sysflag_referential_constraint;
	trigger.fkTrigger = true;
	trigger.relationName = constraint.refRelation;
	trigger.type = POST_MODIFY_TRIGGER;
	trigger.blrData = blrWriter.getBlrData();
}

// Common code factored out.
void RelationNode::generateUnnamedTriggerBeginning(Constraint& constraint, bool onUpdate,
	BlrWriter& blrWriter)
{
	// For ON UPDATE TRIGGER only: generate the trigger firing condition:
	// If prim_key.old_value != prim_key.new value.
	// Note that the key could consist of multiple columns.

	if (onUpdate)
	{
		stuffTriggerFiringCondition(constraint, blrWriter);
		blrWriter.appendUCharRepeated(blr_begin, 2);
	}

	blrWriter.appendUChar(blr_for);
	blrWriter.appendUChar(blr_rse);

	// The context for the prim. key relation.
	blrWriter.appendUChar(1);
	blrWriter.appendUChar(blr_relation);
	blrWriter.appendNullString(0, name.c_str());
	// The context for the foreign key relation.
	blrWriter.appendUChar(2);

	// Generate the blr for: foreign_key == primary_key.
	stuffMatchingBlr(constraint, blrWriter);

	blrWriter.appendUChar(blr_modify);
	blrWriter.appendUChar(2);
	blrWriter.appendUChar(2);
	blrWriter.appendUChar(blr_begin);
}

// The defaultBlr passed is of the form:
//     blr_version4 blr_literal ..... blr_eoc.
// Strip the blr_version4 and blr_eoc verbs and stuff the remaining blr in the blr stream in the
// statement.
void RelationNode::stuffDefaultBlr(const ByteChunk& defaultBlr, BlrWriter& blrWriter)
{
	fb_assert(*defaultBlr.data == blr_version4 || *defaultBlr.data == blr_version5);

	size_t i;

	for (i = 1; i < defaultBlr.length - 1; ++i)
		blrWriter.appendUChar(defaultBlr.data[i]);

	fb_assert(defaultBlr.data[i] == blr_eoc);
}

// Generate blr to express: foreign_key == primary_key
// ie., for_key.column_1 = prim_key.column_1 and
//      for_key.column_2 = prim_key.column_2 and ....  so on.
void RelationNode::stuffMatchingBlr(Constraint& constraint, BlrWriter& blrWriter)
{
	// count of foreign key columns
	fb_assert(constraint.refColumns.getCount() == constraint.columns.getCount());
	fb_assert(constraint.refColumns.getCount() != 0);

	blrWriter.appendUChar(blr_boolean);

	size_t numFields = 0;

	for (ObjectsArray<MetaName>::const_iterator column(constraint.columns.begin()),
			refColumn(constraint.refColumns.begin());
		 column != constraint.columns.end();
		 ++column, ++refColumn, ++numFields)
	{
		if (numFields + 1 < constraint.columns.getCount())
			blrWriter.appendUChar(blr_and);

		blrWriter.appendUChar(blr_eql);

		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(2);
		blrWriter.appendNullString(0, column->c_str());
		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(0);
		blrWriter.appendNullString(0, refColumn->c_str());
	};

	blrWriter.appendUChar(blr_end);
}

// Generate blr to express: if (old.primary_key != new.primary_key).
// Do a column by column comparison.
void RelationNode::stuffTriggerFiringCondition(Constraint& constraint, BlrWriter& blrWriter)
{
	blrWriter.appendUChar(blr_if);

	size_t numFields = 0;

	for (ObjectsArray<MetaName>::const_iterator column(constraint.refColumns.begin());
		 column != constraint.refColumns.end();
		 ++column, ++numFields)
	{
		if (numFields + 1 < constraint.refColumns.getCount())
			blrWriter.appendUChar(blr_or);

		blrWriter.appendUChar(blr_neq);

		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(0);
		blrWriter.appendNullString(0, column->c_str());
		blrWriter.appendUChar(blr_field);
		blrWriter.appendUChar(1);
		blrWriter.appendNullString(0, column->c_str());
	}
}


//----------------------


void CreateRelationNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"CreateRelationNode\n"
		"  name: '%s'\n",
		name.c_str());
}

void CreateRelationNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->tra_attachment;

	saveRelation(tdbb, dsqlScratch, MAKE_cstring(name.c_str()), true);

	if (externalFile)
	{
		fb_assert(dsqlScratch->relation);
		dsqlScratch->relation->rel_flags |= REL_external;
	}

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_CREATE_TABLE, name);

	DYN_UTIL_check_unique_name(tdbb, transaction, name, obj_relation);

	checkRelationTempScope(tdbb, transaction, name, relationType);

	AutoCacheRequest request(tdbb, drq_s_rels2, DYN_REQUESTS);

	STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		REL IN RDB$RELATIONS
	{
		strcpy(REL.RDB$RELATION_NAME, name.c_str());
		REL.RDB$SYSTEM_FLAG = 0;
		REL.RDB$FLAGS = REL_sql;
		REL.RDB$RELATION_TYPE = relationType;

		REL.RDB$VIEW_BLR.NULL = TRUE;
		REL.RDB$VIEW_SOURCE.NULL = TRUE;
		REL.RDB$EXTERNAL_FILE.NULL = TRUE;

		if (externalFile)
		{
			if (externalFile->length() >= sizeof(REL.RDB$EXTERNAL_FILE))
				status_exception::raise(Arg::Gds(isc_dyn_name_longer));

			REL.RDB$EXTERNAL_FILE.NULL = FALSE;
			strcpy(REL.RDB$EXTERNAL_FILE, externalFile->c_str());

			if (ISC_check_if_remote(*externalFile, false))
				status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(163, DYN_MSG_FAC)));

			// Check for any path, present in filename.
			// If miss it, file will be searched in External Tables Dirs,
			// that's why no expand_filename required.

			PathName path, file;
			PathUtils::splitLastComponent(path, file, *externalFile);

			if (path.hasData())	// path component present in filename
			{
				ISC_expand_filename(REL.RDB$EXTERNAL_FILE, strlen(REL.RDB$EXTERNAL_FILE),
					REL.RDB$EXTERNAL_FILE, sizeof(REL.RDB$EXTERNAL_FILE), false);
			}

			REL.RDB$RELATION_TYPE = rel_external;
		}
	}
	END_STORE

	for (const TEXT* p = ALL_PRIVILEGES; *p; ++p)
	{
		request.reset(tdbb, drq_s_usr_prvs, DYN_REQUESTS);

		STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			X IN RDB$USER_PRIVILEGES
		{
			strcpy(X.RDB$RELATION_NAME, name.c_str());
			strcpy(X.RDB$USER, attachment->att_user->usr_user_name.c_str());
			X.RDB$USER_TYPE = obj_user;
			X.RDB$OBJECT_TYPE = obj_relation;
			X.RDB$PRIVILEGE[0] = *p;
			X.RDB$PRIVILEGE[1] = 0;
			X.RDB$GRANT_OPTION = 1;
		}
		END_STORE
	}

	ObjectsArray<Constraint> constraints;
	const dsql_nod* pkCols = findPkColumns();
	SSHORT position = 0;

	for (const dsql_nod* const* i = elements.begin(); i != elements.end(); ++i)
	{
		const dsql_nod* element = *i;

		switch (element->nod_type)
		{
			case Dsql::nod_def_field:
				defineField(tdbb, transaction, element, position, pkCols);
				++position;
				break;

			case Dsql::nod_rel_constraint:
				makeConstraint(tdbb, transaction, element, constraints);
				break;

			default:
				fb_assert(false);
				break;
		}
	}

	for (ObjectsArray<Constraint>::iterator constraint(constraints.begin());
		 constraint != constraints.end();
		 ++constraint)
	{
		defineConstraint(tdbb, transaction, *constraint);
	}

	dsqlScratch->relation->rel_flags &= ~REL_creating;

	executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_CREATE_TABLE, name);

	savePoint.release();	// everything is ok

	// Update DSQL cache
	METD_drop_relation(transaction, name);
	MET_dsql_cache_release(tdbb, SYM_relation, name);
}

// Starting from the elements in a table definition, locate the PK columns if given in a
// separate table constraint declaration.
const dsql_nod* CreateRelationNode::findPkColumns()
{
	for (const dsql_nod* const* i = elements.begin(); i != elements.end(); ++i)
	{
		const dsql_nod* element = *i;

		if (element->nod_type == Dsql::nod_rel_constraint)
		{
			const dsql_nod* node = element->nod_arg[Dsql::e_rct_type];
			if (node->nod_type == Dsql::nod_primary)
				return node->nod_arg[Dsql::e_pri_columns];
		}
	}

	return NULL;
}


//----------------------


void AlterRelationNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"AlterRelationNode\n"
		"  name: '%s'\n",
		name.c_str());
}

void AlterRelationNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	Attachment* attachment = transaction->tra_attachment;

	saveRelation(tdbb, dsqlScratch, MAKE_cstring(name.c_str()), false);

	if (!dsqlScratch->relation)
	{
		TEXT linecol[64];
		sprintf(linecol, "At line %d, column %d.",
			(int) dsqlNode->nod_line, (int) dsqlNode->nod_column);

		status_exception::raise(
			Arg::Gds(isc_sqlerr) << Arg::Num(-204) <<
			Arg::Gds(isc_dsql_relation_err) <<
			Arg::Gds(isc_random) << name <<
			Arg::Gds(isc_random) << linecol);
	}

	// If there is an error, get rid of the cached data.

	try
	{
		// run all statements under savepoint control
		AutoSavePoint savePoint(tdbb, transaction);

		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_TABLE, name);

		ObjectsArray<Constraint> constraints;

		for (const dsql_nod* const* i = elements.begin(); i != elements.end(); ++i)
		{
			const dsql_nod* element = *i;

			switch (element->nod_type)
			{
				case Dsql::nod_def_field:
					defineField(tdbb, transaction, element, -1, NULL);
					break;

				case Dsql::nod_mod_field_type:
					modifyField(tdbb, transaction, element);
					break;

				case Dsql::nod_mod_field_name:
				{
					const dsql_nod* oldField = element->nod_arg[e_mod_fld_name_orig_name];
					MetaName oldFieldName = ((dsql_str*) oldField->nod_arg[e_fln_name])->str_data;
					const dsql_nod* newField = element->nod_arg[e_mod_fld_name_new_name];
					MetaName newFieldName = ((dsql_str*) newField->nod_arg[e_fln_name])->str_data;

					AutoRequest request;
					bool found = false;

					FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
						RFL IN RDB$RELATION_FIELDS
						WITH RFL.RDB$FIELD_NAME EQ oldFieldName.c_str() AND
							 RFL.RDB$RELATION_NAME EQ name.c_str()
					{
						found = true;

						MODIFY RFL
							checkViewDependency(tdbb, transaction, name, oldFieldName);
							checkSpTrigDependency(tdbb, transaction, name, oldFieldName);

							if (!fieldExists(tdbb, transaction, name, newFieldName))
							{
								strcpy(RFL.RDB$FIELD_NAME, newFieldName.c_str());
								AlterDomainNode::modifyLocalFieldIndex(tdbb, transaction, name,
									oldFieldName, newFieldName);
							}
							else
							{
								// msg 205: Cannot rename field %s to %s.  A field with that name
								// already exists in table %s.
								status_exception::raise(
									Arg::Gds(ENCODE_ISC_MSG(205, DYN_MSG_FAC)) <<
										oldFieldName << newFieldName << name);
							}
						END_MODIFY
					}
					END_FOR

					if (!found)
					{
						// msg 176: "column %s does not exist in table/view %s"
						status_exception::raise(
							Arg::Gds(ENCODE_ISC_MSG(176, DYN_MSG_FAC)) << oldFieldName << name);
					}

					break;
				}

				case Dsql::nod_mod_field_null_flag:
				{
					//// FIXME: This clause allows inconsistencies like setting a field with a
					//// not null CONSTRAINT as nullable, or setting a field based on a not null
					//// domain as nullable (while ISQL shows it as not null).

					const dsql_nod* fieldNode = element->nod_arg[e_mod_fld_null_flag_field];
					MetaName fieldName = ((dsql_str*) fieldNode->nod_arg[e_fln_name])->str_data;
					bool flag = element->nod_arg[e_mod_fld_null_flag_value]->getSlong() != 0;

					AutoRequest request;
					bool found = false;

					FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
						RFL IN RDB$RELATION_FIELDS
						WITH RFL.RDB$FIELD_NAME EQ fieldName.c_str() AND
							 RFL.RDB$RELATION_NAME EQ name.c_str()
					{
						found = true;

						MODIFY RFL
							if (!flag && !RFL.RDB$GENERATOR_NAME.NULL)
							{
								// msg 274: Identity column @1 of table @2 cannot be changed to NULLable
								status_exception::raise(
									Arg::Gds(ENCODE_ISC_MSG(274, DYN_MSG_FAC)) << fieldName << name);
							}

							RFL.RDB$NULL_FLAG = SSHORT(flag);
						END_MODIFY
					}
					END_FOR

					if (!found)
					{
						// msg 176: "column %s does not exist in table/view %s"
						status_exception::raise(
							Arg::Gds(ENCODE_ISC_MSG(176, DYN_MSG_FAC)) << fieldName << name);
					}

					break;
				}

				case Dsql::nod_mod_field_pos:
				{
					const dsql_nod* fieldNode = element->nod_arg[e_mod_fld_pos_orig_name];
					MetaName fieldName = ((dsql_str*) fieldNode->nod_arg[e_fln_name])->str_data;
					const dsql_nod* posNode = element->nod_arg[e_mod_fld_pos_new_position];

					// CVC: Since now the parser accepts pos=1..N, let's subtract one here.
					const SSHORT pos = (SSHORT) posNode->getSlong() - 1;

					AutoRequest request;
					bool found = false;
					SSHORT oldPos;

					FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
						RFL IN RDB$RELATION_FIELDS
						WITH RFL.RDB$FIELD_NAME EQ fieldName.c_str() AND
							 RFL.RDB$RELATION_NAME EQ name.c_str()
					{
						found = true;
						oldPos = RFL.RDB$FIELD_POSITION;
					}
					END_FOR

					if (!found)
					{
						// msg 176: "column %s does not exist in table/view %s"
						status_exception::raise(
							Arg::Gds(ENCODE_ISC_MSG(176, DYN_MSG_FAC)) << fieldName << name);
					}

					if (pos != oldPos)
						modifyLocalFieldPosition(tdbb, transaction, name, fieldName, pos, oldPos);

					break;
				}

				case Dsql::nod_del_field:
				{
					// Fix for bug 8054:
					// [CASCADE | RESTRICT] syntax is available in IB4.5, but not
					// required until v5.0.
					//
					// Option CASCADE causes an error: unsupported DSQL construct.
					// Option RESTRICT is default behaviour.

					const dsql_nod* fieldNode = element->nod_arg[0];
					MetaName fieldName = ((dsql_str*) fieldNode->nod_arg[e_fln_name])->str_data;

					if ((element->nod_arg[1])->nod_type == nod_cascade)
					{
						// Unsupported DSQL construct
						status_exception::raise(
							Arg::Gds(isc_sqlerr) << Arg::Num(-901) <<
							Arg::Gds(isc_dsql_command_err) <<
							Arg::Gds(isc_dsql_construct_err));
					}

					fb_assert((element->nod_arg[1])->nod_type == nod_restrict);
					deleteLocalField(tdbb, transaction, name, fieldName);
					break;
				}

				case Dsql::nod_rel_constraint:
					makeConstraint(tdbb, transaction, element, constraints);
					break;

				case Dsql::nod_delete_rel_constraint:
				{
					MetaName constraintName = ((dsql_str*) element->nod_arg[0])->str_data;
					AutoCacheRequest request(tdbb, drq_e_rel_con, DYN_REQUESTS);
					bool found = false;

					FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
						RC IN RDB$RELATION_CONSTRAINTS
						WITH RC.RDB$CONSTRAINT_NAME EQ constraintName.c_str() AND
								RC.RDB$RELATION_NAME EQ name.c_str()
					{
						found = true;
						ERASE RC;
					}
					END_FOR

					if (!found)
					{
						// msg 130: "CONSTRAINT %s does not exist."
						status_exception::raise(
							Arg::Gds(ENCODE_ISC_MSG(130, DYN_MSG_FAC)) << constraintName);
					}

					break;
				}

				default:
					fb_assert(false);
					break;
			}
		}

		for (ObjectsArray<Constraint>::iterator constraint(constraints.begin());
			 constraint != constraints.end();
			 ++constraint)
		{
			defineConstraint(tdbb, transaction, *constraint);
		}

		executeDdlTrigger(tdbb, transaction, DTW_AFTER, DDL_TRIGGER_ALTER_TABLE, name);

		savePoint.release();	// everything is ok

		// Update DSQL cache
		METD_drop_relation(transaction, name);
		MET_dsql_cache_release(tdbb, SYM_relation, name);
	}
	catch (const Exception&)
	{
		METD_drop_relation(transaction, name);
		dsqlScratch->relation = NULL;
		throw;
	}
}

// Modify a field, as part of an alter table statement.
//
// If there are dependencies on the field, abort the operation
// unless the dependency is an index.  In this case, rebuild the
// index once the operation has completed.
//
// If the original datatype of the field was a domain:
//    if the new type is a domain, just make the change to the new domain
//    if it exists
//
//    if the new type is a base type, just make the change
//
// If the original datatype of the field was a base type:
//    if the new type is a base type, just make the change
//
//    if the new type is a domain, make the change to the field
//    definition and remove the entry for RDB$FIELD_SOURCE from the original
//    field.  In other words ... clean up after ourselves
//
// The following conversions are not allowed:
//       Blob to anything
//       Array to anything
//       Date to anything
//       Char to any numeric
//       Varchar to any numeric
//       Anything to Blob
//       Anything to Array
void AlterRelationNode::modifyField(thread_db* tdbb, jrd_tra* transaction, const dsql_nod* element)
{
	Attachment* attachment = transaction->tra_attachment;

	DsqlCompiledStatement* statement = dsqlScratch->getStatement();
	dsql_fld* field = (dsql_fld*) element->nod_arg[Dsql::e_mod_fld_type_field];

	// Add the field to the relation being defined for parsing purposes.
	bool permanent = false;
	dsql_rel* relation = dsqlScratch->relation;

	if (relation)
	{
		if (!(relation->rel_flags & REL_new_relation))
		{
			dsql_fld* permField = FB_NEW(dsqlScratch->getAttachment()->dbb_pool)
				dsql_fld(dsqlScratch->getAttachment()->dbb_pool);
			*permField = *field;

			field = permField;
			permanent = true;
		}

		field->fld_next = relation->rel_fields;
		relation->rel_fields = field;
	}

	try
	{
		dsql_nod* domainNode = element->nod_arg[Dsql::e_mod_fld_type_dom_name];
		dsql_nod* computedNode = element->nod_arg[Dsql::e_mod_fld_type_computed];
		dsql_nod* defaultNode = element->nod_arg[Dsql::e_mod_fld_type_default];
		bool found = false;
		AutoRequest request;

		FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
			RFR IN RDB$RELATION_FIELDS CROSS
			REL IN RDB$RELATIONS CROSS
			FLD IN RDB$FIELDS
			WITH REL.RDB$RELATION_NAME = RFR.RDB$RELATION_NAME AND
				 FLD.RDB$FIELD_NAME = RFR.RDB$FIELD_SOURCE AND
				 RFR.RDB$RELATION_NAME = name.c_str() AND
				 RFR.RDB$FIELD_NAME = field->fld_name.c_str()
		{
			found = true;

			bool isView = !REL.RDB$VIEW_BLR.NULL;

			if (!isView && (!FLD.RDB$COMPUTED_BLR.NULL != (computedNode != NULL)))
			{
				// Cannot add or remove COMPUTED from column @1
				status_exception::raise(
					Arg::Gds(ENCODE_ISC_MSG(249, DYN_MSG_FAC)) << field->fld_name);
			}

			dyn_fld origDom;

			DSC_make_descriptor(&origDom.dyn_dsc, FLD.RDB$FIELD_TYPE, FLD.RDB$FIELD_SCALE,
				FLD.RDB$FIELD_LENGTH, FLD.RDB$FIELD_SUB_TYPE, FLD.RDB$CHARACTER_SET_ID,
				FLD.RDB$COLLATION_ID);

			origDom.dyn_fld_name = field->fld_name;
			origDom.dyn_charbytelen = FLD.RDB$FIELD_LENGTH;
			origDom.dyn_dtype = FLD.RDB$FIELD_TYPE;
			origDom.dyn_precision = FLD.RDB$FIELD_PRECISION;
			origDom.dyn_sub_type = FLD.RDB$FIELD_SUB_TYPE;
			origDom.dyn_charlen = FLD.RDB$CHARACTER_LENGTH;
			origDom.dyn_collation = FLD.RDB$COLLATION_ID;
			origDom.dyn_null_flag = !FLD.RDB$NULL_FLAG.NULL && FLD.RDB$NULL_FLAG != 0;
			origDom.dyn_fld_source = RFR.RDB$FIELD_SOURCE;

			// If the original field type is an array, force its blr type to blr_blob.
			bool hasDimensions = FLD.RDB$DIMENSIONS != 0;
			if (hasDimensions)
				origDom.dyn_dtype = blr_blob;

			bool wasInternalDomain = fb_utils::implicit_domain(origDom.dyn_fld_source.c_str()) &&
				RFR.RDB$BASE_FIELD.NULL;
			string computedSource;
			BlrWriter::BlrData computedValue;

			if (computedNode)
				defineComputed(tdbb, field, computedNode, computedSource, computedValue);

			if (defaultNode)
			{
				MODIFY RFR
					if (defaultNode->nod_type == nod_def_default)
					{
						if (!RFR.RDB$GENERATOR_NAME.NULL)
						{
							// msg 275: Identity column @1 of table @2 cannot have default value
							status_exception::raise(
								Arg::Gds(ENCODE_ISC_MSG(275, DYN_MSG_FAC)) << field->fld_name << name);
						}

						if (hasDimensions)
						{
							// msg 225: "Default value is not allowed for array type in field %s"
							status_exception::raise(
								Arg::Gds(ENCODE_ISC_MSG(225, DYN_MSG_FAC)) << field->fld_name);
						}

						if (computedNode)
						{
							// msg 233: "Local column %s is computed, cannot set a default value"
							status_exception::raise(
								Arg::Gds(ENCODE_ISC_MSG(233, DYN_MSG_FAC)) << field->fld_name);
						}

						string defaultSource;
						BlrWriter::BlrData defaultValue;

						defineDefault(tdbb, field, defaultNode, defaultSource, defaultValue);

						RFR.RDB$DEFAULT_SOURCE.NULL = FALSE;
						attachment->storeMetaDataBlob(tdbb, transaction,
							&RFR.RDB$DEFAULT_SOURCE, defaultSource);

						RFR.RDB$DEFAULT_VALUE.NULL = FALSE;
						attachment->storeBinaryBlob(tdbb, transaction,
							&RFR.RDB$DEFAULT_VALUE, defaultValue);
					}
					else if (defaultNode->nod_type == nod_del_default)
					{
						if (RFR.RDB$DEFAULT_VALUE.NULL)
						{
							if (FLD.RDB$DEFAULT_VALUE.NULL)
							{
								// msg 229: "Local column %s doesn't have a default"
								status_exception::raise(
									Arg::Gds(ENCODE_ISC_MSG(229, DYN_MSG_FAC)) << field->fld_name);
							}
							else
							{
								// msg 230: "Local column %s default belongs to domain %s"
								status_exception::raise(
									Arg::Gds(ENCODE_ISC_MSG(230, DYN_MSG_FAC)) <<
										field->fld_name << MetaName(FLD.RDB$FIELD_NAME));
							}
						}
						else
						{
							RFR.RDB$DEFAULT_SOURCE.NULL = TRUE;
							RFR.RDB$DEFAULT_VALUE.NULL = TRUE;
						}
					}
				END_MODIFY
			}
			else
			{
				// We have the type. Default and type/domain are exclusive for now.

				MetaName newDomainName;
				dyn_fld newDom;

				if (domainNode)
				{
					// Case a1: Internal domain -> domain.
					// Case a2: Domain -> domain.

					const dsql_nod* node1 = domainNode->nod_arg[Dsql::e_dom_name];
					newDomainName = ((dsql_str*) node1->nod_arg[Dsql::e_fln_name])->str_data;

					if (fb_utils::implicit_domain(newDomainName.c_str()))
					{
						// msg 224: "Cannot use the internal domain %s as new type for field %s".
						status_exception::raise(
							Arg::Gds(ENCODE_ISC_MSG(224, DYN_MSG_FAC)) <<
								newDomainName << field->fld_name);
					}

					// Get the domain information.
					if (!METD_get_domain(dsqlScratch->getTransaction(), field, newDomainName.c_str()))
					{
						// Specified domain or source field does not exist.
						status_exception::raise(
							Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
							Arg::Gds(isc_dsql_command_err) <<
							Arg::Gds(isc_dsql_domain_not_found) << newDomainName);
					}

					DDL_resolve_intl_type(dsqlScratch, field, NULL);

					// If the original definition was a base field type, remove the
					// entries from RDB$FIELDS.
					if (wasInternalDomain)
					{
						// Case a1: Internal domain -> domain.
						ERASE FLD;
					}
				}
				else
				{
					// Case b1: Internal domain -> internal domain.
					// Case b2: Domain -> internal domain.

					TypeClause type(field, NULL);

					// If COMPUTED was specified but the type wasn't, we use the type of
					// the computed expression.
					if (computedNode && field->fld_dtype == dtype_unknown)
					{
						dsc desc;
						MAKE_desc(dsqlScratch, &desc, computedNode, NULL);

						field->fld_dtype = desc.dsc_dtype;
						field->fld_length = desc.dsc_length;
						field->fld_scale = desc.dsc_scale;

						if (field->fld_dtype <= dtype_any_text)
						{
							field->fld_character_set_id = DSC_GET_CHARSET(&desc);
							field->fld_collation_id = DSC_GET_COLLATE(&desc);
						}
						else
							field->fld_sub_type = desc.dsc_sub_type;
					}

					type.resolve(dsqlScratch, true);

					if (wasInternalDomain)	// Case b1: Internal domain -> internal domain.
					{
						MODIFY FLD
							updateRdbFields(type,
								FLD.RDB$FIELD_TYPE,
								FLD.RDB$FIELD_LENGTH,
								FLD.RDB$FIELD_SUB_TYPE.NULL, FLD.RDB$FIELD_SUB_TYPE,
								FLD.RDB$FIELD_SCALE.NULL, FLD.RDB$FIELD_SCALE,
								FLD.RDB$CHARACTER_SET_ID.NULL, FLD.RDB$CHARACTER_SET_ID,
								FLD.RDB$CHARACTER_LENGTH.NULL, FLD.RDB$CHARACTER_LENGTH,
								FLD.RDB$FIELD_PRECISION.NULL, FLD.RDB$FIELD_PRECISION,
								FLD.RDB$COLLATION_ID.NULL, FLD.RDB$COLLATION_ID,
								FLD.RDB$SEGMENT_LENGTH.NULL, FLD.RDB$SEGMENT_LENGTH);
						END_MODIFY

						newDom.dyn_fld_source = origDom.dyn_fld_source;
					}
					else	// Case b2: Domain -> internal domain.
						storeGlobalField(tdbb, transaction, newDomainName, type);
				}

				if (!computedNode && !isView)
				{
					if (newDomainName.hasData())
						newDom.dyn_fld_source = newDomainName;

					AlterDomainNode::getDomainType(tdbb, transaction, newDom);
					AlterDomainNode::checkUpdate(origDom, newDom);

					if (!RFR.RDB$GENERATOR_NAME.NULL)
					{
						if (!newDom.dyn_dsc.isExact() || newDom.dyn_dsc.dsc_scale != 0)
						{
							// Identity column @1 of table @2 must be exact numeric with zero scale.
							status_exception::raise(
								Arg::Gds(ENCODE_ISC_MSG(273, DYN_MSG_FAC)) << field->fld_name << name);
						}
					}
				}

				if (newDomainName.hasData())
				{
					MODIFY RFR USING
						RFR.RDB$FIELD_SOURCE.NULL = FALSE;
						strcpy(RFR.RDB$FIELD_SOURCE, newDomainName.c_str());

						if (computedNode)
						{
							RFR.RDB$UPDATE_FLAG.NULL = FALSE;
							RFR.RDB$UPDATE_FLAG = 1;
						}

						RFR.RDB$COLLATION_ID.NULL = TRUE;	// CORE-2426
					END_MODIFY
				}
			}

			if (computedNode)
			{
				// We can alter FLD directly here because if we are setting a computed expression,
				// it means the field already was computed. And if it was, it should be the
				// "b1 case", where the field source does not change.
				// This assumption may change, especially when this function starts dealing
				// with views.

				MODIFY FLD
					FLD.RDB$COMPUTED_SOURCE.NULL = FALSE;
					attachment->storeMetaDataBlob(tdbb, transaction, &FLD.RDB$COMPUTED_SOURCE,
						computedSource);

					FLD.RDB$COMPUTED_BLR.NULL = FALSE;
					attachment->storeBinaryBlob(tdbb, transaction, &FLD.RDB$COMPUTED_BLR,
						computedValue);
				END_MODIFY
			}

			AutoRequest request2;

			FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
				PRM IN RDB$PROCEDURE_PARAMETERS
				WITH PRM.RDB$RELATION_NAME = name.c_str() AND
					 PRM.RDB$FIELD_NAME = field->fld_name.c_str()
			{
				MODIFY PRM USING
					strcpy(PRM.RDB$FIELD_SOURCE, RFR.RDB$FIELD_SOURCE);
				END_MODIFY
			}
			END_FOR

			//// FIXME: Check usage in functions.
		}
		END_FOR

		if (!found)
		{
			// msg 176: "column %s does not exist in table/view %s"
			status_exception::raise(
				Arg::Gds(ENCODE_ISC_MSG(176, DYN_MSG_FAC)) << field->fld_name << name);
		}

		// Update any indices that exist.
		AlterDomainNode::modifyLocalFieldIndex(tdbb, transaction, name,
			field->fld_name, field->fld_name);
	}
	catch (const Exception&)
	{
		clearPermanentField(relation, permanent);
		throw;
	}

	clearPermanentField(relation, permanent);
}


//----------------------


// Delete a global field if it's not used in others objects.
void DropRelationNode::deleteGlobalField(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& globalName)
{
	AutoCacheRequest request(tdbb, drq_e_l_gfld, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		FLD IN RDB$FIELDS
		WITH FLD.RDB$FIELD_NAME EQ globalName.c_str() AND
			 FLD.RDB$VALIDATION_SOURCE MISSING AND
			 FLD.RDB$NULL_FLAG MISSING AND
			 FLD.RDB$DEFAULT_SOURCE MISSING AND
			 FLD.RDB$FIELD_NAME STARTING WITH IMPLICIT_DOMAIN_PREFIX AND
			 (NOT ANY RFR IN RDB$RELATION_FIELDS WITH
				RFR.RDB$FIELD_SOURCE EQ FLD.RDB$FIELD_NAME) AND
			 (NOT ANY PRC IN RDB$PROCEDURE_PARAMETERS WITH
				PRC.RDB$FIELD_SOURCE EQ FLD.RDB$FIELD_NAME)
	{
		DropDomainNode::deleteDimensionRecords(tdbb, transaction, globalName);
		ERASE FLD;
	}
	END_FOR
}

// Remove records from a relation.
void DropRelationNode::erase(thread_db* tdbb, jrd_tra* transaction, const MetaName& name,
	bool view, const string& sqlText)
{
	const int ddlTriggerAction = (view ? DDL_TRIGGER_DROP_VIEW : DDL_TRIGGER_DROP_TABLE);

	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	AutoCacheRequest request(tdbb, drq_l_relation, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		R IN RDB$RELATIONS
		WITH R.RDB$RELATION_NAME EQ name.c_str()
	{
		executeDdlTrigger(tdbb, transaction, DTW_BEFORE, ddlTriggerAction, name, sqlText);
		found = true;
	}
	END_FOR

	request.reset(tdbb, drq_e_rel_con2, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		CRT IN RDB$RELATION_CONSTRAINTS
		WITH CRT.RDB$RELATION_NAME EQ name.c_str() AND
			 (CRT.RDB$CONSTRAINT_TYPE EQ PRIMARY_KEY OR
			  CRT.RDB$CONSTRAINT_TYPE EQ UNIQUE_CNSTRT OR
			  CRT.RDB$CONSTRAINT_TYPE EQ FOREIGN_KEY)
		SORTED BY ASCENDING CRT.RDB$CONSTRAINT_TYPE
	{
		ERASE CRT;
	}
	END_FOR

	request.reset(tdbb, drq_e_rel_idxs, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDX IN RDB$INDICES
		WITH IDX.RDB$RELATION_NAME EQ name.c_str()
	{
		DropIndexNode::deleteSegmentRecords(tdbb, transaction, IDX.RDB$INDEX_NAME);
		ERASE IDX;
	}
	END_FOR

	request.reset(tdbb, drq_e_trg_msgs2, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		TM IN RDB$TRIGGER_MESSAGES
		CROSS T IN RDB$TRIGGERS
		WITH T.RDB$RELATION_NAME EQ name.c_str() AND
			 TM.RDB$TRIGGER_NAME EQ T.RDB$TRIGGER_NAME
	{
		ERASE TM;
	}
	END_FOR

	// CVC: Moved this block here to avoid SF Bug #1111570.
	request.reset(tdbb, drq_e_rel_con3, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		CRT IN RDB$RELATION_CONSTRAINTS
		WITH CRT.RDB$RELATION_NAME EQ name.c_str() AND
			 (CRT.RDB$CONSTRAINT_TYPE EQ CHECK_CNSTRT OR
			  CRT.RDB$CONSTRAINT_TYPE EQ NOT_NULL_CNSTRT)
	{
		ERASE CRT;
	}
	END_FOR

	request.reset(tdbb, drq_e_rel_flds, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		RFR IN RDB$RELATION_FIELDS
		WITH RFR.RDB$RELATION_NAME EQ name.c_str()
	{
		if (!RFR.RDB$GENERATOR_NAME.NULL)
			DropSequenceNode::deleteGenerator(tdbb, transaction, RFR.RDB$GENERATOR_NAME);

		ERASE RFR;

		if (!RFR.RDB$SECURITY_CLASS.NULL &&
			!strncmp(RFR.RDB$SECURITY_CLASS, SQL_SECCLASS_PREFIX, SQL_SECCLASS_PREFIX_LEN))
		{
			deleteSecurityClass(tdbb, transaction, RFR.RDB$SECURITY_CLASS);
		}

		deleteGlobalField(tdbb, transaction, RFR.RDB$FIELD_SOURCE);
	}
	END_FOR

	request.reset(tdbb, drq_e_view_rels, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		VR IN RDB$VIEW_RELATIONS
		WITH VR.RDB$VIEW_NAME EQ name.c_str()
	{
		ERASE VR;
	}
	END_FOR

	request.reset(tdbb, drq_e_relation, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		R IN RDB$RELATIONS
		WITH R.RDB$RELATION_NAME EQ name.c_str()
	{
		ERASE R;

		if (!R.RDB$SECURITY_CLASS.NULL &&
			!strncmp(R.RDB$SECURITY_CLASS, SQL_SECCLASS_PREFIX, SQL_SECCLASS_PREFIX_LEN))
		{
			deleteSecurityClass(tdbb, transaction, R.RDB$SECURITY_CLASS);
		}
	}
	END_FOR

	if (!found)
	{
		// msg 61: "Relation not found"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(61, DYN_MSG_FAC)));
	}

	// Triggers must be deleted after check constraints

	MetaName triggerName;

	request.reset(tdbb, drq_e_trigger2, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		X IN RDB$TRIGGERS
		WITH X.RDB$RELATION_NAME EQ name.c_str()
	{
		triggerName = X.RDB$TRIGGER_NAME;
		ERASE X;

		AutoCacheRequest request2(tdbb, drq_e_trg_prv, DYN_REQUESTS);

		FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
			PRIV IN RDB$USER_PRIVILEGES
			WITH PRIV.RDB$USER EQ triggerName.c_str() AND
					PRIV.RDB$USER_TYPE = obj_trigger
		{
			ERASE PRIV;
		}
		END_FOR
	}
	END_FOR

	request.reset(tdbb, drq_e_usr_prvs, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		PRIV IN RDB$USER_PRIVILEGES
		WITH PRIV.RDB$RELATION_NAME EQ name.c_str() AND
			 PRIV.RDB$OBJECT_TYPE = obj_relation
	{
		ERASE PRIV;
	}
	END_FOR

	request.reset(tdbb, drq_e_view_prv, DYN_REQUESTS);

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		PRIV IN RDB$USER_PRIVILEGES
		WITH PRIV.RDB$USER EQ name.c_str() AND
			 PRIV.RDB$USER_TYPE = obj_view
	{
		ERASE PRIV;
	}
	END_FOR

	if (found)
		executeDdlTrigger(tdbb, transaction, DTW_AFTER, ddlTriggerAction, name, sqlText);
	else
	{
		// msg 61: "Relation not found"
		status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(61, DYN_MSG_FAC)));
	}

	savePoint.release();	// everything is ok
}

void DropRelationNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf(
		"DropRelationNode\n"
		"  name: '%s'\n",
		name.c_str());
}

void DropRelationNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	AutoPtr<dsql_str> nameStr(MAKE_string(name.c_str(), name.length()));
	const dsql_rel* relation = METD_get_relation(transaction, dsqlScratch, nameStr);

	if (!relation && silent)
		return;

	// Check that DROP TABLE is dropping a table and that DROP VIEW is dropping a view.
	if (view)
	{
		if (!relation || (relation && !(relation->rel_flags & REL_view)))
		{
			status_exception::raise(
				Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
				Arg::Gds(isc_dsql_command_err) <<
				Arg::Gds(isc_dsql_view_not_found) << name);
		}
	}
	else
	{
		if (!relation || (relation && (relation->rel_flags & REL_view)))
		{
			status_exception::raise(
				Arg::Gds(isc_sqlerr) << Arg::Num(-607) <<
				Arg::Gds(isc_dsql_command_err) <<
				Arg::Gds(isc_dsql_table_not_found) << name);
		}
	}

	erase(tdbb, transaction, name, view, getSqlText());

	METD_drop_relation(transaction, name.c_str());
	MET_dsql_cache_release(tdbb, SYM_relation, name);
}


//----------------------


void RecreateRelationNode::print(string& text, Array<dsql_nod*>& /*nodes*/) const
{
	text.printf("RecreateRelationNode\n");
}

DdlNode* RecreateRelationNode::internalDsqlPass()
{
	createNode->dsqlPass(dsqlScratch);
	dropNode.dsqlPass(dsqlScratch);
	return DdlNode::internalDsqlPass();
}

void RecreateRelationNode::execute(thread_db* tdbb, jrd_tra* transaction)
{
	// run all statements under savepoint control
	AutoSavePoint savePoint(tdbb, transaction);

	dropNode.execute(tdbb, transaction);
	createNode->execute(tdbb, transaction);

	savePoint.release();	// everything is ok
}


//----------------------


// Store an index.
void CreateIndexNode::store(thread_db* tdbb, jrd_tra* transaction, MetaName& name,
	Definition& definition, MetaName* referredIndexName)
{
	Attachment* attachment = transaction->tra_attachment;

	if (name.isEmpty())
		DYN_UTIL_generate_index_name(tdbb, transaction, name, definition.type);

	DYN_UTIL_check_unique_name(tdbb, transaction, name, obj_index);

	AutoCacheRequest request(tdbb, drq_s_indices, DYN_REQUESTS);

	ULONG keyLength = 0;

	STORE(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDX IN RDB$INDICES
	{
		IDX.RDB$UNIQUE_FLAG.NULL = TRUE;
		IDX.RDB$INDEX_INACTIVE.NULL = TRUE;
		IDX.RDB$INDEX_TYPE.NULL = TRUE;
		IDX.RDB$FOREIGN_KEY.NULL = TRUE;
		IDX.RDB$EXPRESSION_SOURCE.NULL = TRUE;
		IDX.RDB$EXPRESSION_BLR.NULL = TRUE;
		strcpy(IDX.RDB$INDEX_NAME, name.c_str());
		strcpy(IDX.RDB$RELATION_NAME, definition.relation.c_str());
		IDX.RDB$RELATION_NAME.NULL = FALSE;
		IDX.RDB$SYSTEM_FLAG = 0;
		IDX.RDB$SYSTEM_FLAG.NULL = FALSE;

		// Check if the table is actually a view.

		AutoCacheRequest request2(tdbb, drq_l_view_idx, DYN_REQUESTS);

		FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
			VREL IN RDB$RELATIONS
			WITH VREL.RDB$RELATION_NAME EQ IDX.RDB$RELATION_NAME
		{
			if (!VREL.RDB$VIEW_BLR.NULL)
			{
				// msg 181: "attempt to index a view"
				status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(181, DYN_MSG_FAC)));
			}
		}
		END_FOR

		if (definition.unique.specified)
		{
			IDX.RDB$UNIQUE_FLAG.NULL = FALSE;
			IDX.RDB$UNIQUE_FLAG = SSHORT(definition.unique.value);
		}

		if (definition.inactive.specified)
		{
			IDX.RDB$INDEX_INACTIVE.NULL = FALSE;
			IDX.RDB$INDEX_INACTIVE = SSHORT(definition.inactive.value);
		}

		if (definition.descending.specified)
		{
			IDX.RDB$INDEX_TYPE.NULL = FALSE;
			IDX.RDB$INDEX_TYPE = SSHORT(definition.descending.value);
		}

		request2.reset(tdbb, drq_l_lfield, DYN_REQUESTS);

		for (size_t i = 0; i < definition.columns.getCount(); ++i)
		{
			for (size_t j = 0; j < i; ++j)
			{
				if (definition.columns[i] == definition.columns[j])
				{
					// msg 240 "Field %s cannot be used twice in index %s"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(240, DYN_MSG_FAC)) <<
						definition.columns[i] << IDX.RDB$INDEX_NAME);
				}
			}

			bool found = false;

			FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
				F IN RDB$RELATION_FIELDS CROSS
				GF IN RDB$FIELDS
				WITH GF.RDB$FIELD_NAME EQ F.RDB$FIELD_SOURCE AND
					 F.RDB$FIELD_NAME EQ definition.columns[i].c_str() AND
					 IDX.RDB$RELATION_NAME EQ F.RDB$RELATION_NAME
			{
				ULONG length = 0;

				if (GF.RDB$FIELD_TYPE == blr_blob)
				{
					// msg 116 "attempt to index blob field in index %s"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(116, DYN_MSG_FAC)) << IDX.RDB$INDEX_NAME);
				}
				else if (!GF.RDB$DIMENSIONS.NULL)
				{
					// msg 117 "attempt to index array field in index %s"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(117, DYN_MSG_FAC)) << IDX.RDB$INDEX_NAME);
				}
				else if (!GF.RDB$COMPUTED_BLR.NULL)
				{
					// msg 179 "attempt to index COMPUTED BY field in index %s"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(179, DYN_MSG_FAC)) << IDX.RDB$INDEX_NAME);
				}
				else if (GF.RDB$FIELD_TYPE == blr_varying || GF.RDB$FIELD_TYPE == blr_text)
				{
					// Compute the length of the key segment allowing for international
					// information. Note that we we must convert a <character set, collation>
					// type to an index type in order to compute the length.
					if (!F.RDB$COLLATION_ID.NULL)
					{
						length = INTL_key_length(tdbb,
							INTL_TEXT_TO_INDEX(INTL_CS_COLL_TO_TTYPE(
								GF.RDB$CHARACTER_SET_ID, F.RDB$COLLATION_ID)),
							GF.RDB$FIELD_LENGTH);
					}
					else if (!GF.RDB$COLLATION_ID.NULL)
					{
						length = INTL_key_length(tdbb,
							INTL_TEXT_TO_INDEX(INTL_CS_COLL_TO_TTYPE(
								GF.RDB$CHARACTER_SET_ID, GF.RDB$COLLATION_ID)),
							GF.RDB$FIELD_LENGTH);
					}
					else
						length = GF.RDB$FIELD_LENGTH;
				}
				else
					length = sizeof(double);

				if (keyLength)
				{
					keyLength += ((length + STUFF_COUNT - 1) / (unsigned) STUFF_COUNT) *
						(STUFF_COUNT + 1);
				}
				else
					keyLength = length;

				found = true;
			}
			END_FOR

			if (!found)
			{
				// msg 120 "Unknown columns in index %s"
				status_exception::raise(
					Arg::Gds(ENCODE_ISC_MSG(120, DYN_MSG_FAC)) << IDX.RDB$INDEX_NAME);
			}
		}

		if (!definition.expressionBlr.isEmpty())
		{
			IDX.RDB$EXPRESSION_BLR.NULL = FALSE;
			IDX.RDB$EXPRESSION_BLR = definition.expressionBlr;
		}

		if (!definition.expressionSource.isEmpty())
		{
			IDX.RDB$EXPRESSION_SOURCE.NULL = FALSE;
			IDX.RDB$EXPRESSION_SOURCE = definition.expressionSource;
		}

		keyLength = ROUNDUP(keyLength, sizeof(SLONG));
		if (keyLength >= MAX_KEY)
		{
			// msg 118 "key size too big for index %s"
			status_exception::raise(
				Arg::Gds(ENCODE_ISC_MSG(118, DYN_MSG_FAC)) << IDX.RDB$INDEX_NAME);
		}

		if (definition.columns.hasData())
		{
			request2.reset(tdbb, drq_s_idx_segs, DYN_REQUESTS);

			SSHORT position = 0;

			for (ObjectsArray<MetaName>::const_iterator segment(definition.columns.begin());
				 segment != definition.columns.end();
				 ++segment)
			{
				STORE(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
					X IN RDB$INDEX_SEGMENTS
				{
					strcpy(X.RDB$INDEX_NAME, IDX.RDB$INDEX_NAME);
					strcpy(X.RDB$FIELD_NAME, segment->c_str());
					X.RDB$FIELD_POSITION = position++;
				}
				END_STORE
			}
		}
		else if (IDX.RDB$EXPRESSION_BLR.NULL)
		{
			// msg 119 "no keys for index %s"
			status_exception::raise(
				Arg::Gds(ENCODE_ISC_MSG(119, DYN_MSG_FAC)) << IDX.RDB$INDEX_NAME);
		}

		if (definition.refColumns.hasData())
		{
			// If referring columns count <> referred columns return error.

			if (definition.columns.getCount() != definition.refColumns.getCount())
			{
				// msg 133: "Number of referencing columns do not equal number of
				// referenced columns
				status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(133, DYN_MSG_FAC)));
			}

			// Lookup a unique index in the referenced relation with the
			// referenced fields mentioned.

			request2.reset(tdbb, drq_l_unq_idx, DYN_REQUESTS);

			MetaName indexName;
			int listIndex = -1;
			bool found = false;

			FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
				RC IN RDB$RELATION_CONSTRAINTS CROSS
				IND IN RDB$INDICES OVER RDB$INDEX_NAME CROSS
				ISEG IN RDB$INDEX_SEGMENTS OVER RDB$INDEX_NAME
				WITH IND.RDB$RELATION_NAME EQ definition.refRelation.c_str() AND
					 IND.RDB$UNIQUE_FLAG NOT MISSING AND
					 (RC.RDB$CONSTRAINT_TYPE = PRIMARY_KEY OR
					  RC.RDB$CONSTRAINT_TYPE = UNIQUE_CNSTRT)
				SORTED BY IND.RDB$INDEX_NAME,
						  DESCENDING ISEG.RDB$FIELD_POSITION
			{
				if (indexName != IND.RDB$INDEX_NAME)
				{
					if (listIndex >= 0)
						found = false;
					if (found)
						break;
					listIndex = definition.refColumns.getCount() - 1;
					indexName = IND.RDB$INDEX_NAME;
					found = true;
				}

				// If there are no more fields or the field name doesn't
				// match, then this is not the correct index.

				if (listIndex >= 0)
				{
					fb_utils::exact_name_limit(ISEG.RDB$FIELD_NAME, sizeof(ISEG.RDB$FIELD_NAME));
					if (definition.refColumns[listIndex--] != ISEG.RDB$FIELD_NAME)
						found = false;
				}
				else
					found = false;
			}
			END_FOR

			if (listIndex >= 0)
				found = false;

			if (found)
			{
				IDX.RDB$FOREIGN_KEY.NULL = FALSE;
				strcpy(IDX.RDB$FOREIGN_KEY, indexName.c_str());

				if (referredIndexName)
					*referredIndexName = indexName;
			}
			else
			{
				AutoRequest request3;
				bool isView = false;

				FOR(REQUEST_HANDLE request3 TRANSACTION_HANDLE transaction)
					X IN RDB$RELATIONS
					WITH X.RDB$RELATION_NAME EQ definition.refRelation.c_str()
				{
					found = true;
					isView = !X.RDB$VIEW_BLR.NULL;
				}
				END_FOR

				if (isView)
				{
					// msg 242: "attempt to reference a view (%s) in a foreign key"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(242, DYN_MSG_FAC)) << definition.refRelation);
				}

				if (found)
				{
					// msg 18: "could not find UNIQUE or PRIMARY KEY constraint in table %s with
					// specified columns"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(18, DYN_MSG_FAC)) << definition.refRelation);
				}
				else
				{
					// msg 241: "Table %s not found"
					status_exception::raise(
						Arg::Gds(ENCODE_ISC_MSG(241, DYN_MSG_FAC)) << definition.refRelation);
				}
			}
		}
		else if (definition.refRelation.hasData())
		{
			request2.reset(tdbb, drq_l_primary, DYN_REQUESTS);

			FOR(REQUEST_HANDLE request2 TRANSACTION_HANDLE transaction)
				IND IN RDB$INDICES CROSS
				RC IN RDB$RELATION_CONSTRAINTS OVER RDB$INDEX_NAME
				WITH IND.RDB$RELATION_NAME EQ definition.refRelation.c_str() AND
					 RC.RDB$CONSTRAINT_TYPE EQ PRIMARY_KEY
			{
				// Number of columns in referred index should be same as number
				// of columns in referring index.

				fb_assert(IND.RDB$SEGMENT_COUNT >= 0);
				if (definition.columns.getCount() != ULONG(IND.RDB$SEGMENT_COUNT))
				{
					// msg 133: "Number of referencing columns do not equal number of
					// referenced columns"
					status_exception::raise(Arg::Gds(ENCODE_ISC_MSG(133, DYN_MSG_FAC)));
				}

				fb_utils::exact_name_limit(IND.RDB$INDEX_NAME, sizeof(IND.RDB$INDEX_NAME));

				IDX.RDB$FOREIGN_KEY.NULL = FALSE;
				strcpy(IDX.RDB$FOREIGN_KEY, IND.RDB$INDEX_NAME);

				if (referredIndexName)
					*referredIndexName = IND.RDB$INDEX_NAME;
			}
			END_FOR

			if (IDX.RDB$FOREIGN_KEY.NULL)
			{
				// msg 20: "could not find PRIMARY KEY index in specified table %s"
				status_exception::raise(
					Arg::Gds(ENCODE_ISC_MSG(20, DYN_MSG_FAC)) << definition.refRelation);
			}
		}

		IDX.RDB$SEGMENT_COUNT = SSHORT(definition.columns.getCount());
	}
	END_STORE
}


//----------------------


// Delete the records in RDB$INDEX_SEGMENTS pertaining to an index.
bool DropIndexNode::deleteSegmentRecords(thread_db* tdbb, jrd_tra* transaction,
	const MetaName& name)
{
	AutoCacheRequest request(tdbb, drq_e_idx_segs, DYN_REQUESTS);
	bool found = false;

	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
		IDXSEG IN RDB$INDEX_SEGMENTS WITH IDXSEG.RDB$INDEX_NAME EQ name.c_str()
	{
		found = true;
		ERASE IDXSEG;
	}
	END_FOR

	return found;
}


}	// namespace Jrd