From 4599805c7f719de8795b6ecf2b0d1d25fa2ca693 Mon Sep 17 00:00:00 2001
From: asfernandes <asfernandes@users.sourceforge.net>
Date: Thu, 7 Sep 2006 03:30:31 +0000
Subject: [PATCH] Detect ambiguities in implicit MATCHING of views in REPLACE

---
 src/common/classes/GenericMap.h | 27 +++++++++++++---
 src/common/classes/tree.h       |  5 +--
 src/dsql/metd.epp               | 55 +++++++++++++++++++++++----------
 3 files changed, 64 insertions(+), 23 deletions(-)

diff --git a/src/common/classes/GenericMap.h b/src/common/classes/GenericMap.h
index 2bc3f56482..0dcb9fc552 100644
--- a/src/common/classes/GenericMap.h
+++ b/src/common/classes/GenericMap.h
@@ -67,6 +67,28 @@ public:
 	GenericMap() : tree(&getPool()), mCount(0) { }
 	GenericMap(MemoryPool& a_pool) : AutoStorage(a_pool), tree(&getPool()), mCount(0) { }
 	~GenericMap() {
+		clear();
+	}
+
+	void takeOwnership(GenericMap& from) {
+		clear();
+
+		tree = from.tree;
+		mCount = from.mCount;
+
+		if (from.tree.getFirst()) {
+			while (true) {
+				bool haveMore = from.tree.fastRemove();
+				if (!haveMore)
+					break;
+			}
+		}
+
+		from.mCount = 0;
+	}
+
+	// Clear the map
+	void clear() {
 		if (tree.getFirst()) {
 			while (true) {
 				KeyValuePair* temp = tree.current();
@@ -75,11 +97,8 @@ public:
 				if (!haveMore) break;
 			}
 		}
-	}
 
-	// Clear the map
-	void clear() {
-		tree.clear();
+		mCount = 0;
 	}
 
 	// Returns true if value existed
diff --git a/src/common/classes/tree.h b/src/common/classes/tree.h
index e1f4cd95c3..5476c58942 100644
--- a/src/common/classes/tree.h
+++ b/src/common/classes/tree.h
@@ -115,9 +115,10 @@ public:
 		append(from);
 	}
 
-	BePlusTree& operator=(const BePlusTree& from) {
+	BePlusTree& operator =(BePlusTree& from) {
 		clear();
 		append(from);
+		return *this;
 	}
 
 	void clear() {
@@ -245,7 +246,7 @@ public:
 		return ((NodeList*)root)->getCount() * bytes_per_node;
 	}
 
-	void append(const BePlusTree& from) {
+	void append(BePlusTree& from) {
 		// This is slow approach especially when used for assignment. 
 		// Optimize it when need arises.
 		Accessor accessor(&from);
diff --git a/src/dsql/metd.epp b/src/dsql/metd.epp
index cb59b134cd..800ff12ee2 100644
--- a/src/dsql/metd.epp
+++ b/src/dsql/metd.epp
@@ -1791,6 +1791,8 @@ dsql_rel* METD_get_view_base(dsql_req* request,
  *  is more than one.
  *  If there is only one base, put in fields a map of
  *  top view field name / bottom base field name.
+ *  Ignores the field in the case of a base field name
+ *  appearing more than one time in a level.
  *
  **************************************/
 
@@ -1801,7 +1803,7 @@ dsql_rel* METD_get_view_base(dsql_req* request,
 	isc_db_handle DB = dbb->dbb_database_handle;
 	bool first = true;
 	bool cont = true;
-	MetaNamePairMap aux;
+	MetaNamePairMap previousAux;
 
 	fields.clear();
 
@@ -1832,6 +1834,9 @@ dsql_rel* METD_get_view_base(dsql_req* request,
 			relation = METD_get_relation(request, relation_name);
 			delete relation_name;
 
+			Firebird::Array<Firebird::MetaName> ambiguities;
+			MetaNamePairMap currentAux;
+
 			THREAD_EXIT();
 
 			if (!relation)
@@ -1847,33 +1852,49 @@ dsql_rel* METD_get_view_base(dsql_req* request,
 
 				THREAD_ENTER();
 
-				if (first)
-				{
-					fields.put(
-						(RFL.RDB$FIELD_NAME.NULL ? "" : RFL.RDB$FIELD_NAME),
-						(RFL.RDB$BASE_FIELD.NULL ? "" : RFL.RDB$BASE_FIELD));
+				if (RFL.RDB$BASE_FIELD.NULL)
+					RFL.RDB$BASE_FIELD[0] = '\0';
 
-					aux.put(
-						(RFL.RDB$BASE_FIELD.NULL ? "" : RFL.RDB$BASE_FIELD),
-						(RFL.RDB$FIELD_NAME.NULL ? "" : RFL.RDB$FIELD_NAME));
-				}
+				if (RFL.RDB$FIELD_NAME.NULL)
+					RFL.RDB$FIELD_NAME[0] = '\0';
+
+				if (currentAux.exist(RFL.RDB$BASE_FIELD))
+					ambiguities.add(RFL.RDB$BASE_FIELD);
 				else
 				{
-					Firebird::MetaName field;
-
-					if (aux.get(RFL.RDB$FIELD_NAME, field))
+					if (first)
 					{
-						fields.put(field,
-							(RFL.RDB$BASE_FIELD.NULL ? "" : RFL.RDB$BASE_FIELD));
+						fields.put(RFL.RDB$FIELD_NAME, RFL.RDB$BASE_FIELD);
+						currentAux.put(RFL.RDB$BASE_FIELD, RFL.RDB$FIELD_NAME);
+					}
+					else
+					{
+						Firebird::MetaName field;
 
-						aux.remove(RFL.RDB$FIELD_NAME);
-						aux.put((RFL.RDB$BASE_FIELD.NULL ? "" : RFL.RDB$BASE_FIELD), field);
+						if (previousAux.get(RFL.RDB$FIELD_NAME, field))
+						{
+							fields.put(field, RFL.RDB$BASE_FIELD);
+							currentAux.put(RFL.RDB$BASE_FIELD, field);
+						}
 					}
 				}
 
 				THREAD_EXIT();
 			END_FOR
 
+			for (Firebird::MetaName* i = ambiguities.begin(); i != ambiguities.end(); ++i)
+			{
+				Firebird::MetaName field;
+
+				if (currentAux.get(*i, field))
+				{
+					currentAux.remove(*i);
+					fields.remove(field);
+				}
+			}
+
+			previousAux.takeOwnership(currentAux);
+
 			if (relation->rel_flags & REL_view)
 				view_name = X.RDB$RELATION_NAME;
 			else