firebird-mirror/doc/WhatsNew

  **************
  * v2.0 Alpha 1
  **************
  
    * Cleanup
        Command line switch L for SuperServer is no longer recognized as the old local protocol was deleted.
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Security improvement
        Another layout of security.fdb
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * Fixed unregistered bug
        Column-level privileges are preserved after this column is dropped
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed unregistered bug
        Memory leak when selectable stored procedures are called from PSQL or in subqueries
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Index improvements
        Don't check uniqueness for null keys
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * SQL improvements
        1) Introduced SEQUENCE as a synonym for GENERATOR (as per SQL-99)
        2) Added SQL-99 compliant NEXT VALUE FOR <sequence_name> expression
        3) Implemented REVOKE ADMIN OPTION FROM statement
      See also:
        /doc/sql.extentions/README.sequence_generators
        /doc/sql.extentions/README.ddl.txt
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed unregistered bug
        Backup issues with stream BLOBs
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Diagnostics about missing/unusable UDF module
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * Optimizer improvements
        1) Distribute HAVING clause conjunctions to the WHERE clause when possible
        2) Distribute UNION conjunctions to the inner streams when possible
        3) Improved cross join and merge/sort handling
        4) Better optimization of mixed AND/OR predicates
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>
        Dmitry Yemanov <yemanov at yandex.ru>

    * SQL improvement
        Supported UDFs to be called as procedures (i.e. ignoring their output) in PSQL
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * ISQL improvement:
        Command line switch -b to bail out on error when used in non-interactive mode.
        Also, return an error code to the operating system.
      See also:
        /doc/README.isql_enhancements.txt
      Contributor(s):
        Damyan Ivanov <divanov at creditreform.bg>
        Claudio Valderrama <cvalde at usa.net>

    * Context variables
        Added support for context variables via RDB$GET_CONTEXT and RDB$SET_CONTEXT system functions
      See also:
        /doc/sql.extentions/README.context_variables2
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed SF #1065511
        XP SP2 slow to connect to Linux server
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed bugs SF #459059 and #543106
        1) index breaks = ANY result
        2) bug with ALL keyword
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * ODS change
        Enlarged exception messages from 78 to 1021 bytes
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * Fixed bug SF #1057538
        UDF output parameter not being the last crashes the server
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Fixed unregistered bug
        System users "AUTHENTICATOR" and "SWEEPER" were lost, causing "SQL SERVER" to be reported instead
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * Configuration change
        Added new parameter LegacyHash to firebird.conf
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * Security improvements
        1) New (more secure) password hash calculation algorithm
        2) Ability for users to modify their own passwords
        3) Rejected any remote (non-embedded) access to security.fdb
        4) Use Services API in GSEC
        5) Protect from attempts to brute-force accounts/passwords
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * Configuration change
        Added new parameter GCPolicy to firebird.conf
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * Garbage collection improvements
        New GC thread implementation and combined cooperative + background activity
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * Fixed unregistered bug
        Some cases where ambiguous queries were still possible
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * ODS change
        Added RDB$DESCRIPTION to RDB$GENERATORS
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * CURRENT_TIMESTAMP and 'NOW' improvements
        Return milliseconds when a current timestamp is asked for
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * SQL improvement
        Allowed PLAN, ROWS and ORDER BY clauses in UPDATE/DELETE statements
      See also:
        /doc/sql.extentions/README.select_expressions
      Contributor(s):
      	Oleg Loa <loa at mail.ru>

    * 64-bit builds
        A number of changes (including ODS support) to support Firebird on 64-bit platforms
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Reworked constraint checking logic
        More precise checks for PK/UK/FK constraints
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * SQL improvement
        Added an equivalence predicate which behaves exactly as equality/inequality, but treats NULL = NULL as TRUE
      Syntax:
        A IS [NOT] DISTINCT FROM B
      See also:
        /doc/sql.extentions/README.distinct
      Contributor(s):
      	Oleg Loa <loa at mail.ru>
        Dmitry Yemanov <yemanov at yandex.ru>

    * SQL improvements
        1) Allowed FIRST/SKIP/ROWS/PLAN and ORDER BY clauses in views
        2) Added CROSS JOIN (A CROSS JOIN B means something like A INNER JOIN B ON 1 = 1 or just FROM A, B)
        3) Allowed UNION in subqueries and INSERT statement
      See also:
        /doc/sql.extentions/README.select_expressions
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * New transaction option
        Added lock timeouts for WAIT transactions (see new TPB value isc_tpb_lock_timeout)
      Contributor(s):
        Aleksey Karyakin <karyakin at cmpmail.com>
        Dmitry Yemanov <yemanov at yandex.ru>

    * WNET protocol changes
        WNET (aka NetBEUI) protocol no longer performs client impersonation
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed unregistered bug
        Introduced 40-bit (64-bit internally) record numbers to avoid ~30GB table size limit
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Buffer cache improvements
        1) Much faster algorithms to process the dirty pages tree
        2) Increased maximum page cache size to 128K pages (2GB for 16K page size)
      Contributor(s):
      	Oleg Loa <loa at mail.ru>
        Dmitry Yemanov <yemanov at yandex.ru>

    * Security improvements
        Fixed a number of known vulnerabilities in API
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>
        Alex Peshkov <peshkoff at mail.ru>

    * Fixed unregistered bug
        Don't rollback prepared 2PC sub-transaction
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * Server log improvement
        Add filename and line number to BUGCHECK log messages
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * GSEC improvement
        Now GSEC returns the error code when used as a non-interactive utility
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Fixed unregistered bug
        Server crash with DECLARE FILTER
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * SQL extention
        Allowed UNION DISTINCT as a synonym for simple UNION (as per SQL-99 spec)
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed bug SF #571026
        INET/INET_connect: gethostbyname
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed bug SF #223058
        Multi-hop server ability broken
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Optimizer improvement
        Let's choose a reasonable join order for intermixed inner and outer joins
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Configuration change
        Added new parameter UsePriorityScheduler to firebird.conf
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * ISQL improvement
        ODS version is now shown as a part of SHOW DATABASE command
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Minor BLOB improvement
        Introduced BLOB SUB_TYPE BINARY as a synonym for SUB_TYPE 0
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * ODS change
        Introduced a concept of ODS type to be able to distinguish between InterBase databases, Firebird databases, databases created by debug builds of Firebird and private forks
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * UDF improvement
        Ability to signal SQL NULL via a NULL pointer
      See also:
        /doc/sql.extentions/README.ddl.txt
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Expression indices
        Implemented indices based on arbitrary expressions
      Syntax:
        CREATE [UNIQUE] [ASC[ENDING] | DESC[ENDING]] INDEX <index_name> ON <table_name> ( <value_expression> )
      See also:
        /doc/sql.extentions/README.expression_indices
      Contributor(s):
      	Oleg Loa <loa at mail.ru>
        Dmitry Yemanov <yemanov at yandex.ru>

    * IIF builtin function
        Added IIF (<search_condition>, <value1>, <value2>) as a shortcut for CASE WHEN <search_condition> THEN <value1> ELSE <value2> END
      See also:
        /doc/sql.extentions/README.iif
      Contributor(s):
      	Oleg Loa <loa at mail.ru>

    * Fixed unregistered bug
        A number of possible server crashes, as reported by Valgrind
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * IN/OR improvements
        Constant IN predicate or multiple OR booleans are now evaluated faster
      Contributor(s):
      	Oleg Loa <loa at mail.ru>

    * NULL becomes a syntactical value
        You may now specify A = NULL, B > NULL, etc (all of them evaluate to FALSE)
      See also:
        /doc/sql.extentions/README.null_value
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Concatenation overflow
        A compile-time check has been dropped in favour of the runtime one
      Contributor(s):
      	Oleg Loa <loa at mail.ru>
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed unregistered bug
        Issues with dates below Julian date stored in indices
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * PSQL stack trace
        Added ability to report a PSQL stack trace when exception occurs
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * OLD context changes
        Reject any assignment to the OLD trigger context (e.g. make it read-only)
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Index scan imporvement
        NULLs are ignored during the index scan (when it makes sense)
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * Fixed bug SF #735720
        SELECT ... STARTING WITH :v is wrong when :v = ''
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * Fixed unregistered bug
        Crash when changing data type for field and specify wrong type or domain name
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * ODS change
        Added RDB$DESCRIPTION and RDB$SYSTEM_FLAG to RDB$ROLES
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Fixed some BLOB issues
        1) Outrageous memory consumption when blobs are converted from strings during request processing
        2) Materialization doesn't cause invalidation of BLOB IDs too early
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Problems with UDF argument mapping to parameters
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Server crash due to incorrect accounting of attachment pointers used inside the lock structure
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Improved ISQL
        1) Fixed bug SF #223126 - Misplaced collation when extracting metadadata with ISQL
        2) Fixed bug SF #223513 - Ambiguity between tables and views
        3) Fixed bug SF #518349 - ISQL show mangles relationship
      Contributor(s):
        Blas Rodriguez Somoza <blas at puertareal.com>

    * Fixed bug SF #910423
        ALTER TABLE altering to VARCHAR
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Improved ISQL
        1) Fixed bug SF #910430 - ISQL and database dialect
        2) Add SET HEADING ON/OFF option
        3) Add -M2 command-line option to send output of statistics and plans to the same file than the rest of the output
      See also:
        /doc/README.isql_enhancements.txt
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Fixed unregistered bug
        Rounding problems in date/time arithmetics
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Wrong counting of line numbers in DSQL parser when multi-line literals and identifiers are used
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed v1.5 bug
        Random crash on restore
      Contributor(s):
        Jim Starkey <jas at netfrastructure.com>

    * Fixed unregistered bug
        Crash/lock-up with multiple calls of isc_dsql_prepare for a single statement (like IBO does)
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Server crash when too big/small system year is set up
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * User-defined plans improvements
        1) Propagate plan fragments to nested levels of joins, thus allowing to manually optimize complex outer joins
        2) Check the user-supplied plan for correctness in outer joins
        3) Added short-circuit optimization for user-supplied plans
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed unregistered bug
        Server crash when the stream number exceeds the limit
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed unregistered bug.
        Memory leak in EXECUTE STATEMENT
      Contributor(s):
        Alex Peshkov <peshkoff at mail.ru>

    * Fixed unregistered bug
        UDF arguments are being prepared/optimized twice
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Index structure improvements
        More effective compressing
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * New database shutdown modes are introduced
        Single-user and full shutdown modes are implemented
      See also:
        /doc/README.shutdown_modes.txt
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Memory leak during conversion from string to blob
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * C/C++ client interface version added
        FB_API_VER defined to 20 for Firebird 2.0 in ibase.h
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Implemented EXECUTE BLOCK statement
        It is now possible to use dynamic PSQL with this statement
      See also:
        /doc/sql.extentions/README.execute_block
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * Implemented support for default parameters for stored procedures
      See also:
        /doc/sql.extentions/README.default_parameters
      Contributor(s):
        Vlad Horsun <horsun at kdb.dp.ua>

    * DSQL parser changed
        It now always detects table aliases ambiguity and abandoned support for implicit double table aliases
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * Fixed unregistered bug
        Problems with interdependent views during restore process
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * Fixed SF #750664
        Issues with read-only databases and transactions
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Fixed memory leak from connection pool in isc_database_info
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Per-segment index selectivity maintenance
        Per-segment selectivity information is now available to the optimizer opening possibilities for more clever access path decisions
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>
        Arno Brinkman <firebird at abvisie.nl>

    * Fixed/re-worked invariant tracking in PSQL and request cloning logic
        This fixes numerous issues with recursive procedures, for example SF #627057
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Re-worked logic of updatable views
        This solves problems with views that are implicitly updatable, but still have update triggers
      See also:
        /doc/sql.extentions/README.view_updates
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Added SQL200X ROWS clause
        New syntax to limit amount of records you want to get
      See also:
        /doc/sql.extentions/README.rows
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fixed SF #781610
        Problems with -- comments in ISQL
      Contributor(s):
        John Bellardo <bellardo at cs.ucsd.edu>
        Blas Rodriguez Somoza <blas at puertareal.com>

    * Support for explicit cursor syntax in PSQL
        It is now possible to declare and use multiple cursors in PSQL
      See also:
        /doc/sql.extentions/README.cursors
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * LIKE/CONTAINING/STARTING WITH functions re-worked
        1) functions now work with BLOBs correctly
        2) use single-pass Knuth-Morris-Pratt algorithm for pattern matching
        3) fix crash when NULL is used as ESCAPE character for LIKE
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Fixed unregistered bug
        Fixed server crash with explicit plans used in subqueries, when outer aggregation is performed.
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Nulls ordering is changed to be SQL200X-compliant (SF #225218)
        Implemented nulls placement behavior is MSSQL-like, works on ODS11 databases only since it requires new indices for operation. 
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Enable support for databases on raw devices
        You can now use raw devices to store database. Exceptionally usable with database aliases
      Contributor(s):
        Erik Kunze <erik.kunze at philosys.de>
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * New indices code
        Very fast, nicely tolerates large amount of duplicates, limit of 256 bytes key length removed
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * Internal logging enhanced
        1) Implemented thread- and signal- safe debug logging facilities
        2) Updated routines that print out various internal structures (DSQL node tree, BLR, DYN, etc)
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Improved PLAN clause
        Allowed to specify more possible paths for the engine
      Example:
        PLAN (A ORDER IDX1 INDEX (IDX2, IDX3))
      See also:
        /doc/sql.extentions/README.plan
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Further optimizer improvements
        1) MERGE PLAN may now be generated for joins using equality comparsion on expressions
        2) Better logic regarding unique indices handling
        3) Improved logic for OR expressions
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * New local protocol
        XNET is now used as local protocol for Windows and is supported in CS builds
      See also:
        /doc/README.xnet
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Services API are fully ported to Classic architecture
        All Services API are supported on Linux and Windows CS
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * SUBSTRING enhanced
        SUBSTRING built-in function now supports arbitrary expressions in parameters
      Contributor(s):
      	Oleg Loa <loa at mail.ru>
        Dmitry Yemanov <yemanov at yandex.ru>

    * Added LEAVE <label> syntax support
        PSQL loops now may be marked with labels and terminated in Java style
      See also:
        /doc/sql.extentions/README.leave_labels
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Improved ROW_COUNT
        Now it's possible to get number of selected rows as well
      See also:
        /doc/sql.extentions/README.context_variables
      Contributor(s):
        Dmitry Yemanov <yemanov at yandex.ru>

    * Fix SF #750659
        Generators values were resisting metadata-only backup
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Fix SF #544132, #728839
        Problems with nulls handling in UDFs
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Fix SF #784121
        Problems with some expressions in outer join conditions
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>

    * Slightly reworked synchronization logic
        1) Significantly reduce thread lock contention in lock manager and in SuperServer thread pool manager
        2) Fix rare race condition that could cause SS engine to hang during request processing until next request arrival
        3) Make lock manager memory dumps more informative (OWN_hung is detected correctly)
        4) Decouple lock manager synchronization objects for different engine instances
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Derived tables support
        Implemented support for derived tables in DSQL (subqueries in FROM clause) as defined by SQL200X
      See also:
        /doc/sql.extentions/README.derived_tables.txt
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * Enhanced GROUP BY clause
        Implemented support for arbitrary expressions in GROUP BY clause
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * UNION enhanced
        Fixed field type coersion logic in unions
      Contributor(s):
        Arno Brinkman <firebird at abvisie.nl>

    * New backup technology
        Implemented fast on-line physical incremental backup facilities
      See also:
        /doc/README.nbackup.txt
      Contributor(s):
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Generic cleanup.
        Various cleaning and tidying up of code, warnings removal, 64-bitness cleanup, numerous minor bugfixes
      Contributor(s):
        Blas Rodriguez Somoza <blas at puertareal.com>
        Dmitry Yemanov <yemanov at yandex.ru>
        Nickolay Samofatov <nickolay at broadviewsoftware.com>

    * Generic cleanup
        Large amount of ongoing code cleanup and style standardization. In particular, broken WAL and journalling code is fully cleaned out
      Contributor(s):
        Claudio Valderrama <cvalde at usa.net>