HISTORY

                                 Release Notes

                                  Release 7.3

     Release date: 2002-??-??

Overview

   Major changes in this release:

   Schemas

           Schemas allow users to create objects in their own namespace
           so two people or applications can have tables with the same
           name. There is also a public schema for shared tables.
           Table/index creation can be restricted by removing
           permissions on the public schema.

   Drop Column

           PostgreSQL now supports ALTER TABLE ... DROP COLUMN functionality.

   Table Functions

           Functions returning multiple rows and/or multiple columns are
           now much easier to use than before.  You can call such a
           "table function" in the SELECT FROM clause, treating its output
           like a table. Also, plpgsql functions can now return sets.

   Prepared Queries

           For performance, PostgreSQL now supports prepared queries.

   Dependency Tracking

           PostgreSQL now records object dependencies, which allows
           improvements in many areas.

   Privileges

           Functions and procedural languages now have privileges, and
           people running them can take on the privileges of their creators.

   Multibyte/Locale

           Both multibyte and locale are now always enabled.

   Logging

           A variety of logging options have been enhanced.

   Interfaces

           A large number of interfaces have been moved to 
           http://gborg.postgresql.org where they can be developed
           and released independently.

   Functions/Identifiers

           By default, functions can now take up to 32 parameters, and 
           identifiers can be up to 63 bytes long.

     ----------------------------------------------------------------------

Migration to version 7.3

   A dump/restore using "pg_dump" is required for those wishing to migrate
   data from any previous release.  A summary of changes needed in client
   applications is at 
   http://www.ca.postgresql.org/docs/momjian/upgrade_tips_7.3.

   Observe the following incompatibilities:

     * Pre-6.3 clients are no longer supported.

     * pg_hba.conf now has a USER column and additional features.

     * Several GUC logging parameters have been renamed and improved.

     * LIMIT #,# is disabled, use LIMIT # OFFSET #.

     * LIMIT can now appear before FOR UPDATE, for portability.

     * INSERTs with column lists must specify all values, e.g. 
       INSERT INTO tab (col1, col2) VALUES ('val1') is now invalid

     * DROP object now takes either CASCADE or RESTRICT to control
       whether dependent objects are also dropped

     * An index is now not automatically created for SERIAL columns

     * A SET inside an aborted transaction is now rolled back

     * COPY no longer considers missing trailing columns to be NULL

     * TIMESTAMP and TIME data types now default to WITHOUT TIMEZONE

     * Pre-7.3 databases loaded into 7.3 will not have the new object
       dependencies for SERIAL, UNIQUE constraints, and foreign keys. See
       /contrib/adddepend for a detailed description and a script that
       will add the such dependencies.

     ----------------------------------------------------------------------

Changes

2002-09-23

Server Operation
================
Kerberos V Heimdal support (KTH)
Add pg_locks view to show locks (Neil)
Security fixes for password negotiation memory allocation (Neil)
Remove support for version 0, <=6.2 FE/BE protocol (Tom)
Reserve the last few backend slots for superusers, add GUC variable
  superuser_reserved_connections to control this (Nigel J. Andrews)

Performance
===========
Improve startup by calling localtime() only once (Tom)
Cache system catalog information in flat files for faster startup (Tom)
Improve caching of index information (Tom)
Optimizer improvements (Tom, Fernando Nasser)
Catalog caches now store failed lookups (Tom)
Hash function improvements (Neil)
Improve performance of query tokenization and network handling (Peter)
Speed improvement for large object restore (Mario Weilguni)
Mark expired index entries on first lookup, saving later heap fetches (Tom)
Eliminate NULL bitmap padding when not required (Manfred)
Add BSD-licensed qsort() for Solaris, for performance (Bruce)
Reduce per-row overhead by four bytes (Manfred Koizar)
Fix GEQO optimizer bug (Neil Conway)
Make WITHOUT OID actually save four bytes per row (Manfred Koizar)
Add GUC default_statistics_target variable to specify ANALYZE buckets (Neil)
Use local buffer cache for temporary tables so no WAL overhead (Tom)
Improve free space map performance on large tables (Stephen Marshall, Tom)

Privileges
==========
Add privileges on functions and procedural languages (Peter)
Add OWNER to CREATE DATABASE so superusers can create databases
  on behalf of unprivileged users.  (Gavin Sherry, Tom)
Add new object permission bits EXECUTE and USAGE (Tom)
Add SET SESSION AUTHORIZATION DEFAULT and RESET SESSION AUTHORIZATION (Peter)
Allow functions to be executed with the privilege of the function owner (Peter)

Client Authentication
=====================
Allow $HOME/.pgpass to store host/user password combinations (Alvaro Herrera)

Server Configuration
====================
Server log messages now tagged with LOG, not DEBUG (Bruce)
Add USER column to pg_hba.conf (Bruce)
Have log_connections output two lines in log file (Tom)
Remove debug_level from postgresql.conf, now SERVER_MIN_MESSAGES (Bruce)
New ALTER DATABASE/USER ... SET command for per-user/db initialization (Peter)
New GUC variables server_min_messages and client_min_messages which control
  which messages are sent to the server logs or client applications (Bruce)
Allow pg_hba.conf to specify lists of users/dbs separated by commas, 
  group names prepended with +, and file names prepended with @ (Bruce)
Allow group names specified by +
Add samegroup in pg_hba.conf for group name/dbname restriction (Bruce)
Remove secondary password file capability (Bruce)
Remove pg_passwd utility (Bruce)
Add GUC variable db_user_namespace for db-local user names (Bruce)
SSL improvements (Bear Giles)
Make encryption of stored passwords the default (Bruce)
Allow pg_statistics to be reset by calling pg_stat_reset() (Christopher)
Add log_duration GUC parameter (Bruce)
Rename GUC debug_print_query to log_statement (Bruce)
Rename GUC show_query_stats to show_statement_stats (Bruce)
Add GUC param log_min_error_statement to print query to logs on error (Gavin)

Queries
=======
Make cursors insensitive, meaning their contents do not change (Tom)
Disable LIMIT #,# syntax; now only LIMIT # OFFSET # supported (Bruce)
Increase identifier length to 64 (Neil, Bruce)
UNION fixes for merging >= 3 columns of different lengths (Tom)
Add DEFAULT keyword to INSERT, i.e INSERT ... (..., DEFAULT, ) (Rod)
Allow views to have default values using ALTER COLUMN ... SET DEFAULT (Neil)
Fail on INSERTs with column lists that don't supply all column values,
  e.g. INSERT INTO tab (col1, col2) VALUES ('val1');  (Rod)
Fix for join aliases (Tom)
Fix for FULL OUTER JOINs (Tom)
Improve reporting of invalid identifier and location (Tom, Gavin)
Fix OPEN cursor(args) (Tom)
Allow 'ctid' to be used in a view and currtid(viewname) (Hiroshi)
Fix for CREATE TABLE AS with UNION (Tom)
SQL99 syntax improvements (Thomas)
Add GUC statement_timeout variable to cancel queries (Bruce)
Allow prepared queries with PREPARE/EXECUTE (Neil)
Allow FOR UPDATE to appear after LIMIT/OFFSET (Bruce)
Add auto-transactions with GUC variable autocommit (Tom, David Van Wie)

Object Manipulation
===================
Make equals signs optional in CREATE DATABASE (Gavin Sherry)
Make ALTER TABLE OWNER to change index ownership (Neil)
Add per-database and per-user startup commands, ALTER DATABASE ... SET and 
  ALTER USER ... SET (Peter)
New ALTER TABLE tabname ALTER COLUMN colname SET STORAGE controls TOAST
  storage, compression (John Gray)
Add SCHEMA support with CREATE/DROP SCHEMA (Tom)
Create schema for temporary tables (Tom)
Add GUC variable search_path for namespace schema search (Tom)
Add ALTER TABLE SET/DROP NOT NULL (Christopher)
New CREATE FUNCTION volatility levels (Tom)
Make rule names unique only per table (Tom)
Add 'ON tablename' clause to DROP RULE and COMMENT ON RULE (Tom)
Add ALTER TRIGGER RENAME (Joe)
New current_schema() and current_schemas() inquiry functions (Tom)
Allow functions to return multiple rows, also called table functions (Joe)
Make WITH optional in CREATE DATABASE, for consistency (Bruce)
Add object dependency tracking (Rod, Tom)
Add RESTRICT/CASCADE to DROP commands (Rod)
Add ALTER TABLE DROP non-CHECK CONSTRAINT (Rod)
Auto-destroy sequence on DROP of table with SERIAL (Rod)
Prevent column dropping if column is used by foreign key (Rod)
Automatically drop constraints/functions when object is dropped (Rod)
Add CREATE/DROP OPERATOR CLASS (Bill Studenmund, Tom)
Add ALTER TABLE DROP COLUMN (Christopher, Tom, Hiroshi)
Prevent inherited columns from being removed or renamed (Alvaro Herrera)
Add CREATE OR REPLACE VIEW, CREATE OR REPLACE RULE (Gavin, Neil, Tom)
Fix foreign key constraints to not error on intermediate db states (Stephan)
Propagate column or table renaming to foreign key constraints
Add CREATE OR REPLACE VIEW (Gavin, Neil, Tom)
Add CREATE OR REPLACE RULE (Gavin, Neil, Tom)

Utility Commands
================
Have COPY TO output embedded carriage returns and newlines as \r and \n (Tom)
Allow DELIMITER in COPY FROM to be 8-bit clean (Tatsuo)
Make pg_dump use ALTER TABLE ADD PRIMARY KEY, for performance (Neil)
Disable brackets in multi-statement rules (Bruce)
Disable VACUUM from being called inside a function (Bruce)
Allow dropdb and other scripts to use identifiers with spaces (Bruce)
Restrict comment to the current database
Allow comments on operators, independent of the underlying function (Rod)
Rollback SET commands in aborted transactions (Tom)
EXPLAIN now outputs as a query (Tom)
Display sort keys in EXPLAIN (Tom)
Add 'SET LOCAL var = value' to set GUC variables for a single transaction (Tom)
Allow ANALYZE to run in a transaction (Bruce)
Improve COPY syntax using new WITH clauses, keep backward compatibility (Bruce)
Fix pg_dump to consistently output tags in non-ASCII dumps (Bruce)
Make foreign key constraints clearer in dump file (Rod)
Add COMMENT ON CONSTRAINT (Rod)
Allow COPY TO/FROM to specify column names (Brent Verner)
Dump UNIQUE and PRIMARY KEY contraints as ALTER TABLE (Rod)
Have SHOW output a query result (Joe)
Generate failure on short COPY lines rather than pad NULLs (Neil)
Fix CLUSTER to preserve all table attributes (Alvaro Herrera)
New pg_settings table to view/modify GUC settings (Joe)
Add smart quoting, portability improvements to pg_dump output (Peter)
Dump serial columns out as SERIAL (Tom)
Enable large file support, >2G for pg_dump (Peter)
Disallow TRUNCATE on tables that are involved in referential constraints (Rod)
Have TRUNCATE also auto-truncate the toast table of the relation (Tom)
Add clusterdb utility that will auto-cluster an entire database based on
  previous CLUSTER operations (Alvaro Herrera)
Overhaul pg_dumpall (Peter)
Allow REINDEX of TOAST tables (Tom)
Implemented START TRANSACTION, per SQL99 (Neil)

Data Types and Functions
========================
Fix factorial(0) to return 1 (Bruce)
Date/time/timezone improvements (Thomas)
Fix for array slice extraction (Tom)
Fix extract/date_part to report proper microseconds for timestamp (Tatsuo)
Allow text_substr() and bytea_substr() to read TOAST values more
  efficiently (John Gray)
Add DOMAIN type support (Rod)
Make WITHOUT TIME ZONE the default for TIMESTAMP and TIME data types (Thomas)
Allow alternate storage scheme of 64-bit integers for date/time types
  using --enable-integer-datetimes in configure (Thomas)
Make timezone(timestamptz) return timestamp rather than a string (Thomas)
Allow fractional seconds in date/time types for dates prior to 1BC (Thomas)
Limit timestamp data types to 6 decimal places of precision (Thomas)
Change timezone conversion functions from timetz() to timezone() (Thomas)
Add GUC variables datestyle and timezone (Tom)
Add OVERLAY(), which allows substitution of a substring in a string (Thomas)
Add SIMILAR TO as a synonym for our existing operator "~" (Thomas, Tom)
Add regular expression SUBSTRING(string FROM pat FOR escape) (Thomas)
Add LOCALTIME and LOCALTIMESTAMP functions (Thomas)
Add named composite types using CREATE TYPE typename AS (column) (Joe)
Allow composite type definition in the table alias clause (Joe)
Add new API to simplify creation of C language table functions (Joe)
Remove ODBC-compatible empty parentheses from calls to SQL99 functions
 for which these parentheses do not match the standar (Thomas)
Add appendix in the User's Guide which lists SQL92 features (Thomas)
Allow macaddr data type to accept 12 hex digits with no separators (Mike Wyer)
Add CREATE/DROP CAST (Thomas)
Add IS DISTINCT FROM operator (Thomas)
Add SQL99 TREAT() function, synonym for CAST() (Thomas)
Add pg_backend_pid() to output backend pid (Bruce)
Allow inet arrays in /contrib/array (Neil)
Add IS OF / IS NOT OF type predicate (Thomas)
Allow bit string constants without fully-specified length (Thomas)
Allow conversion between 8-byte integers and bit strings (Thomas)
Implement hex literal conversion to bit string literal (Thomas)
Allow table functions to appear in the FROM clause (Joe)
Increase maximum number of function parameters to 32 (Bruce)
No longer automatically create index for SERIAL column (Tom)
Add current_database() (Rod)
Fix cash_words() to not overflow buffer (Tom)
Add functions replace(), split_part(), to_hex() (Joe)
Fix LIKE for bytea as a right-hand argument (Joe)
Prevent crashes caused by SELECT cash_out(2)
Triggers are now fired in alphabetical order (Tom)
Add /contrib/adddepend to handle pre-7.3 object dependencies (Rod)
Allow better casting when INSERTing/UPDATing values (Tom)
Fix to_char(1,'FM999.99') to return a period (Karel)
Fix trigger/type/language functions returning OPAQUE to return proper type (Tom)

Internationalization
====================
Add additional encodings (Korean (JOHAB), Thai (WIN874), Vietnamese (TCVN), 
  Arabic (WIN1256), Simplified Chinese (GBK), Korean (UHC) (Eiji Tokuya)
Enable locale support by default (Peter)
Add GUC locale variables (Peter)
Escape byes >= 0x7f for multibyte in PQescapeBytea/PQunescapeBytea (Tatsuo)
Add locale awareness to regular expression character classes
Enable multibyte support by default (Tatso)
Add GUC variables client_encoding (Tom)
Add GB18030 multibyte support (Bill Huang)
Add CREATE/DROP CONVERSION, allowing loadable encodings (Tatsuo, Kaori)
Add pg_conversion table (Tatsuo)
Add SQL99 CONVERT() function (Tatsuo)

Server-side Languages
=====================
Allow recursive SQL function (Peter)
Change PL/Tcl build to use configured compiler and Makefile.shlib (Peter)
Overhaul the PL/pgSQL FOUND variable to be more Oracle-compatible (Tom, Neil)
Allow PL/pgSQL to handle quoted identifiers (Tom)
Allow PL/pgSQL functions can return sets (Neil)

Psql
====
Don't lowercase psql \connect database name for 7.2.0 compatibility (Tom)
Add psql \timing to time user queries (Greg Sabino Mullane)
Have psql \d show index information (Greg Sabino Mullane)
New psql \dD shows domains (Jonathan Eisler)
Allow psql to show rules on views (Paul ?)
Fix for psql variable substitution (Tom)
Allow psql \d to show temporary table structure (Tom)
Allow psql \d to show foreign keys (Rod)
Fix \? to honor \pset pager (Bruce)
Have psql reports its version number on startup (Tom)

Libpq
=====
Add PQunescapeBytea() function to libpq (Patrick Welche)
Fix for sending large queries over non-blocking connections (Bernhard Herzog)
Fix for libpq using timers on Win9X (David Ford)
Allow libpq notify to handle servers with different-length identifiers (Tom)
Add libpq PQescapeString() and PQescapeBytea() to Win32 (Bruce)
Fix for SSL with non-blocking connections (Jack Bates)
Add libpq connection timeout parameter (Denis A Ustimenko)

JDBC
====
Allow jdbc to compile with jdk 1.4 (Dave)
Add jdbc3 support (Barry)
Allows jdbc to set loglevel by adding ?loglevel=X to the connection URL (Barry)
Add jdbc Driver.info() message that prints out the version number (Barry)
Add jdbc updateable result sets
Add jdbc support for callable statements
Add jdbc query cancel capability
Add refresh row to jdbc (Dave)
Fix jdbc MD5 encryption handling for multibyte servers (Jun Kawai)
Add JDBC support for prepared statements (Barry)
Add support for new prepared statements

ECPG
====
Fixed ecpg bug concerning octal numbers in single quotes (Michael)

Misc. Interfaces
================
Move /interfaces/libpgeasy to http://gborg.postgresql.org (Marc, Bruce)
Improve python (Elliot Lee, Andrew Johnson, Greg Copeland)
Add libpgtcl connection close event (Gerhard Hintermayer)
Move /interfaces/libpq++ to http://gborg.postgresql.org (Marc, Bruce)
Move /interfaces/odbc to http://gborg.postgresql.org (Marc)
Move /interfaces/libpgeasy to http://gborg.postgresql.org (Marc, Bruce)
Move /interfaces/perl5 to http://gborg.postgresql.org (Marc, Bruce)
Remove /bin/pgaccess from main tree, now at http://www.pgaccess.org (Bruce)
Add pg_on_connection_loss command to libpgtcl (Gerhard Hintermayer, Tom)

Build and Install
=================
Fix for parallel make (Peter)
AIX fixes for linking TCL (Andreas Zeugswetter)
Allow plperl to build under Cygwin (Jason Tishler)
Improve MIPS compiles (Peter, Oliver Elphick)
Require autoconf version 2.53 (Peter)
Require readline and zlib by default in configure (Peter)
Allow Solaris to use Intimate Shared Memory (ISM), for performance
  (Scott Brunza, P.J. Josh Rovero)
Always enable syslog in compile, remove --enable-syslog option (Tatsuo)
Always enable multibyte in compile, remove --enable-multibyte option (Tatsuo)
Always enable locale in compile, remove --enable-locale option (Tatsuo)
Fix for Win9x DLL creation (Magnus Naeslund)
Fix for link() usage by WAL code on Win32, Netware, BeOS (Jason Tishler)
Add sys/types.h to c.h, remove from main files (Peter, Bruce)
Fix AIX hang on SMP machines (Tomoyuki Niijima)
AIX SMP hang fix (Tomoyuki Niijima)
Fix pre-1970 date handling on newer glibc libraries (Tom)
Fix PowerPC SMP locking (Tom)
Prevent gcc -ffast-math from being used (Tom)

Source Code
===========
Improve loadable module linking to use RTLD_NOW (Tom)
New error levels WARNING, INFO, LOG, DEBUG[1-5] (Bruce)
New src/port directory holds replace libc functions (Peter, Bruce)
New pg_namespace system catalog for schemas (Tom)
Add pg_class.relnamespace for schemas (Tom)
Add pg_type.typnamespace for schemas (Tom)
Add pg_proc.pronamespace for schemas (Tom)
Restructure aggregates to have pg_proc entries (Tom)
System relations now have their own namespace, pg_* test not required
  (Fernando Nasser)
Rename TOAST index names to be *_index rather than *_idx (Neil)
Add namespaces for operators, opclasses (Tom)
Add additional checks to server control file (Thomas)
New Polish FAQ (Marcin Mazurek)
Add Posix semaphore support (Tom)
Document need for reindex (Bruce)
Rename some internal identifiers to simplify Win32 compile (Jan, Katherine Ward)
Add documentation on computing disk space (Bruce)
Remove KSQO from GUC (Bruce)
Fix memory leak in rtree (Kenneth Been)
Modify a few error messages for consistency (Bruce)
Remove unused system table columns (Peter)
Make system columns NOT NULL where appropriate (Tom)
Clean up use of sprintf in favor of snprintf() (Neil, Jukka Holappa)
Remove OPAQUE and create specific subtypes (Tom)
Cleanups in array internal handling (Joe, Tom)
Disallow pg_atoi('') (Bruce)
Remove GUC parameter wal_files because WAL files are now recycled (Bruce)
Add version numbers to heap pages (Tom)


Contrib
=======
Gist fixes (Teodor Sigaev, Neil)
Upgrade /contrib/mysql
Add /contrib/dbsize which shows table sizes without vacuum (Peter)
Add /contrib/intagg, integer aggregator routines (mlw)
Improve /contrib/Oid2name (Neil, Bruce)
Improve /contrib/tsearch (Teodor Sigaev)
Improve /contrib/tsearch (Oleg)
Cleanups of /contrib/rserver (Alexey V. Borzov)
Update /contrib/oracle conversion utility (Gilles Darold)
Update /contrib/dblink (Joe)
Improve options supported by /contrib/vacuumlo (Mario Weilguni)
Improvements to /contrib/intarray (Oleg, Teodor Sigaev, Andrey Oktyabrski)
Add /contrib/reindexdb utility (Shaun Thomas)
Add indexing to /contrib/isbn_issn (Dan Weston)
Add /contrib/dbmirror (Steven Singer)
Improve /contrib/pgbench (Neil)
Add /contrib/tablefunc table function examples (Joe)
Add /contrib/ltree data type for tree structures (Teodor Sigaev, Oleg Bartunov)
Move /contrib/pg_controldata into main tree (Bruce)
Fixes to /contrib/cube (Bruno Wolff)
Improve /contrib/fulltextindex (Christopher)


     ----------------------------------------------------------------------

                                 Release 7.2.3

     Release date: 2002-10-01

   This has a variety of fixes from 7.2.2, including fixes to prevent
   possible data loss.

     ----------------------------------------------------------------------

Migration to version 7.2.3

   A dump/restore is *not* required for those running 7.2.X.

     ----------------------------------------------------------------------

Changes

 Prevent possible compressed transaction log loss (Tom)
 Prevent non-superuser from increasing most recent vacuum info (Tom)
 Handle pre-1970 date values in newer versions of glibc (Tom)
 Fix possible hang during server shutdown
 Prevent spinlock hangs on SMP PPC machines (Tomoyuki Niijima)
 Fix pg_dump to properly dump FULL JOIN USING (Tom)


     ----------------------------------------------------------------------

                                 Release 7.2.2

     Release date: 2002-08-23

   This has a variety of fixes from 7.2.1, including the security
   problems reported on BUGTRAQ.

     ----------------------------------------------------------------------

Migration to version 7.2.2

   A dump/restore is *not* required for those running 7.2.X.

     ----------------------------------------------------------------------

Changes

 Allow EXECUTE of "CREATE TABLE AS ... SELECT" in PL/pgSQL (Tom)
 Fix for compressed transaction log id wraparound (Tom)
 Fix PQescapeBytea/PQunescapeBytea so that they handle bytes > 0x7f (Tatsuo)
 Fix for psql and pg_dump crashing when invoked with non-existent long 
   options (Tatsuo)
 Fix crash when invoking geometric operators (Tom)
 Allow OPEN cursor(args) (Tom)
 Fix for rtree_gist index build (Teodor)
 Fix for usage of partial indexes for relations other than first in
   joins (Tom)
 Fix for dumping user-defined aggregates (Tom)
 Contrib/intarray fixes (Oleg)
 Fix for complex UNION/EXCEPT/INTERSECT queries using parens (Tom)
 Fix to pg_convert (Tatsuo)
 Fix for buffer overrun in handling long datetime input (Thomas, Neil)
 Fix for buffer overrun in repeat() (Neil)
 Fix for buffer overrun in lpad() and rpad() with multibyte (Neil)
 Fix for buffer overrun in SET TIME ZONE and TZ env var (Neil)


     ----------------------------------------------------------------------

                                 Release 7.2.1

     Release date: 2002-03-21

   This has a variety of fixes from 7.2.

     ----------------------------------------------------------------------

Migration to version 7.2.1

   A dump/restore is *not* required for those running 7.2.

     ----------------------------------------------------------------------

Changes

 Ensure that sequence counters do not go backwards after a crash (Tom)
 Fix pgaccess kanji-coversion key binding (Tatsuo)
 Optimizer improvements (Tom)
 cash I/O improvements (Tom)
 New Russian FAQ
 Compile fix for missing AuthBlockSig (Heiko)
 Additional time zones and time zone fixes (Thomas)
 Allow psql \connect to handle mixed case database and user names (Tom)
 Return proper OID on command completion even with ON INSERT rules (Tom)
 Allow COPY FROM to use 8-bit DELIMITERS (Tatsuo)
 Fix bug in extract/date_part for milliseconds/microseconds (Tatsuo)
 Improve handling of multiple UNIONs with different lengths (Tom)
 contrib/btree_gist improvements (Teodor Sigaev)
 contrib/tsearch dictionary improvements, see README.tsearch for
   an additional installation step (Thomas T. Thai, Teodor Sigaev)
 Fix for array subscripts handling (Tom)
 Allow EXECUTE of "CREATE TABLE AS ... SELECT" in PL/pgSQL (Tom)


     ----------------------------------------------------------------------

                                  Release 7.2

     Release date: 2002-02-04

Overview

   This release improves PostgreSQL for use in high-volume applications.

   Major changes in this release:

   VACUUM

           Vacuuming no longer locks tables, thus allowing normal user access
           during the vacuum. A new "VACUUM FULL" command does old-style
           vacuum by locking the table and shrinking the on-disk copy of the
           table.

   Transactions

           There is no longer a problem with installations that exceed four
           billion transactions.

   OID's

           OID's are now optional. Users can now create tables without OID's
           for cases where OID usage is excessive.

   Optimizer

           The system now computes histogram column statistics during
           "ANALYZE", allowing much better optimizer choices.

   Security

           A new MD5 encryption option allows more secure storage and
           transfer of passwords. A new Unix-domain socket authentication
           option is available on Linux and BSD systems.

   Statistics

           Administrators can use the new table access statistics module to
           get fine-grained information about table and index usage.

   Internationalization

           Program and library messages can now be displayed in several
           languages.

     ----------------------------------------------------------------------

Migration to version 7.2

   A dump/restore using "pg_dump" is required for those wishing to migrate
   data from any previous release.

   Observe the following incompatibilities:

     * The semantics of the "VACUUM" command have changed in this release.
       You may wish to update your maintenance procedures accordingly.

     * In this release, comparisons using = NULL will always return false (or
       NULL, more precisely). Previous releases automatically transformed
       this syntax to IS NULL. The old behavior can be re-enabled using a
       "postgresql.conf" parameter.

     * The "pg_hba.conf" and "pg_ident.conf" configuration is now only
       reloaded after receiving a SIGHUP signal, not with each connection.

     * The function "octet_length()" now returns the uncompressed data
       length.

     * The date/time value 'current' is no longer available. You will need to
       rewrite your applications.

     * The timestamp() function is no longer available.  Use timestamp
       'string' instead, or CAST.

   The SELECT ... LIMIT #,# syntax will be removed in the next release. You
   should change your queries to use separate LIMIT and OFFSET clauses, e.g.
   LIMIT 10 OFFSET 20.

     ----------------------------------------------------------------------

Changes

  Server Operation

   Create temporary files in a separate directory (Bruce)
   Delete orphanded temporary files on postmaster startup (Bruce)
   Added unique indexes to some system tables (Tom)
   System table operator reorganization (Oleg Bartunov, Teodor Sigaev, Tom)
   Renamed pg_log to pg_clog (Tom)
   Enable SIGTERM, SIGQUIT to kill backends (Jan)
   Removed compile-time limit on number of backends (Tom)
   Better cleanup for semaphore resource failure (Tatsuo, Tom)
   Allow safe transaction ID wraparound (Tom)
   Removed OID's from some system tables (Tom)
   Removed "triggered data change violation" error check (Tom)
   SPI portal creation of prepared/saved plans (Jan)
   Allow SPI column functions to work for system columns (Tom)
   Long value compression improvement (Tom)
   Statistics collector for table, index access (Jan)
   Truncate extra-long sequence names to a reasonable value (Tom)
   Measure transaction times in milliseconds (Thomas)
   Fix TID sequential scans (Hiroshi)
   Superuser ID now fixed at 1 (Peter E)
   New pg_ctl "reload" option (Tom)

     ----------------------------------------------------------------------

  Performance

   Optimizer improvements (Tom)
   New histogram column statistics for optimizer (Tom)
   Reuse write-ahead log files rather than discarding them (Tom)
   Cache improvements (Tom)
   IS NULL, IS NOT NULL optimizer improvement (Tom)
   Improve lock manager to reduce lock contention (Tom)
   Keep relcache entries for index access support functions (Tom)
   Allow better selectivity with NaN and infinities in NUMERIC (Tom)
   R-tree performance improvements (Kenneth Been)
   B-tree splits more efficient (Tom)

     ----------------------------------------------------------------------

  Privileges

   Change UPDATE, DELETE permissions to be distinct (Peter E)
   New REFERENCES, TRIGGER privileges (Peter E)
   Allow GRANT/REVOKE to/from more than one user at a time (Peter E)
   New has_table_privilege() function (Joe Conway)
   Allow non-superuser to vacuum database (Tom)
   New SET SESSION AUTHORIZATION command (Peter E)
   Fix bug in privilege modifications on newly created tables (Tom)
   Disallow access to pg_statistic for non-superuser, add user-accessible views (Tom)

     ----------------------------------------------------------------------

  Client Authentication

   Fork postmaster before doing authentication to prevent hangs (Peter E)
   Add ident authentication over Unix domain sockets on Linux, *BSD (Helge Bahmann, Oliver Elphick, Teodor Sigaev, Bruce)
   Add a password authentication method that uses MD5 encryption (Bruce)
   Allow encryption of stored passwords using MD5 (Bruce)
   PAM authentication (Dominic J. Eidson)
   Load pg_hba.conf and pg_ident.conf only on startup and SIGHUP (Bruce)

     ----------------------------------------------------------------------

  Server Configuration

   Interpretation of some time zone abbreviations as Australian rather than North American now settable at run time (Bruce)
   New parameter to set default transaction isolation level (Peter E)
   New parameter to enable conversion of "expr = NULL" into "expr IS NULL", off by default (Peter E)
   New parameter to control memory usage by VACUUM (Tom)
   New parameter to set client authentication timeout (Tom)
   New parameter to set maximum number of open files (Tom)

     ----------------------------------------------------------------------

  Queries

   Statements added by INSERT rules now execute after the INSERT (Jan)
   Prevent unadorned relation names in target list (Bruce)
   NULLs now sort after all normal values in ORDER BY (Tom)
   New IS UNKNOWN, IS NOT UNKNOWN Boolean tests (Tom)
   New SHARE UPDATE EXCLUSIVE lock mode (Tom)
   New EXPLAIN ANALYZE command that shows run times and row counts (Martijn van Oosterhout)
   Fix problem with LIMIT and subqueries (Tom)
   Fix for LIMIT, DISTINCT ON pushed into subqueryies (Tom)
   Fix nested EXCEPT/INTERSECT (Tom)

     ----------------------------------------------------------------------

  Schema Manipulation

   Fix SERIAL in temporary tables (Bruce)
   Allow temporary sequences (Bruce)
   Sequences now use int8 internally (Tom)
   New SERIAL8 creates int8 columns with sequences, default still SERIAL4 (Tom)
   Make OIDs optional using WITHOUT OIDS (Tom)
   Add %TYPE syntax to CREATE TYPE (Ian Lance Taylor)
   Add ALTER TABLE / DROP CONSTRAINT for CHECK constraints (Christopher Kings-Lynne)
   New CREATE OR REPLACE FUNCTION to alter existing function (preserving the function OID) (Gavin Sherry)
   Add ALTER TABLE / ADD [ UNIQUE | PRIMARY ] (Christopher Kings-Lynne)
   Allow column renaming in views
   Make ALTER TABLE / RENAME COLUMN update column names of indexes (Brent Verner)
   Fix for ALTER TABLE / ADD CONSTRAINT ... CHECK with inherited tables (Stephan Szabo)
   ALTER TABLE RENAME update foreign-key trigger arguments correctly (Brent Verner)
   DROP AGGREGATE and COMMENT ON AGGREGATE now accept an aggtype (Tom)
   Add automatic return type data casting for SQL functions (Tom)
   Allow GiST indexes to handle NULLs and multikey indexes (Oleg Bartunov, Teodor Sigaev, Tom)
   Enable partial indexes (Martijn van Oosterhout)

     ----------------------------------------------------------------------

  Utility Commands

   Add RESET ALL, SHOW ALL (Marko Kreen)
   CREATE/ALTER USER/GROUP now allow options in any order (Vince)
   Add LOCK A, B, C functionality (Neil Padgett)
   New ENCRYPTED/UNENCRYPTED option to CREATE/ALTER USER (Bruce)
   New light-weight VACUUM does not lock table; old semantics are available as VACUUM FULL (Tom)
   Disable COPY TO/FROM on views (Bruce)
   COPY DELIMITERS string must be exactly one character (Tom)
   VACUUM warning about index tuples fewer than heap now only appears when appropriate (Martijn van Oosterhout)
   Fix permission checks for CREATE INDEX (Tom)
   Disallow inappropriate use of CREATE/DROP INDEX/TRIGGER/VIEW (Tom)

     ----------------------------------------------------------------------

  Data Types and Functions

   SUM(), AVG(), COUNT() now uses int8 internally for speed (Tom)
   Add convert(), convert2() (Tatsuo)
   New function bit_length() (Peter E)
   Make the "n" in CHAR(n)/VARCHAR(n) represents letters, not bytes (Tatsuo)
   CHAR(), VARCHAR() now reject strings that are too long (Peter E)
   BIT VARYING now rejects bit strings that are too long (Peter E)
   BIT now rejects bit strings that do not match declared size (Peter E)
   INET, CIDR text conversion functions (Alex Pilosov)
   INET, CIDR operators << and <<= indexable (Alex Pilosov)
   Bytea \### now requires valid three digit octal number
   Bytea comparison improvements, now supports =, <>, >, >=, <, and <=
   Bytea now supports B-tree indexes
   Bytea now supports LIKE, LIKE...ESCAPE, NOT LIKE, NOT LIKE...ESCAPE
   Bytea now supports concatenation
   New bytea functions: position, substring, trim, btrim, and length
   New encode() function mode, "escaped", converts minimally escaped bytea to/from text
   Add pg_database_encoding_max_length() (Tatsuo)
   Add pg_client_encoding() function (Tatsuo)
   now() returns time with millisecond precision (Thomas)
   New TIMESTAMP WITHOUT TIMEZONE data type (Thomas)
   Add ISO date/time specification with "T", yyyy-mm-ddThh:mm:ss (Thomas)
   New xid/int comparison functions (Hiroshi)
   Add precision to TIME, TIMESTAMP, and INVERVAL data types (Thomas)
   Modify type coersion logic to attempt binary-compatible functions first (Tom)
   New encode() function installed by default (Marko Kreen)
   Improved to_*() conversion functions (Karel Zak)
   Optimize LIKE/ILIKE when using single-byte encodings (Tatsuo)
   New functions in contrib/pgcrypto: crypt(), hmac(), encrypt(), gen_salt() (Marko Kreen)
   Correct description of translate() function (Bruce)
   Add INTERVAL argument for SET TIME ZONE (Thomas)
   Add INTERVAL YEAR TO MONTH (etc.) syntax (Thomas)
   Optimize length functions when using single-byte encodings (Tatsuo)
   Fix path_inter, path_distance, path_length, dist_ppath to handle closed paths (Curtis Barrett, Tom)
   octet_length(text) now returns non-compressed length (Tatsuo, Bruce)
   Handle "July" full name in date/time literals (Greg Sabino Mullane)
   Some datatype() function calls now evaluated differently
   Add support for Julian and ISO time specifications (Thomas)

     ----------------------------------------------------------------------

  Internationalization

   National language support in psql, pg_dump, libpq, and server (Peter E)
   Message translations in Chinese (simplified, traditional), Czech, French, German, Hungarian, Russian, Swedish (Peter E, Serguei A. Mokhov, Karel Zak, Weiping He, Zhenbang Wei, Kovacs Zoltan)
   Make trim, ltrim, rtrim, btrim, lpad, rpad, translate multibyte aware (Tatsuo)
   Add LATIN5,6,7,8,9,10 support (Tatsuo)
   Add ISO 8859-5,6,7,8 support (Tatsuo)
   Correct LATIN5 to mean ISO-8859-9, not ISO-8859-5 (Tatsuo)
   Make mic2ascii() non-ASCII aware (Tatsuo)
   Reject invalid multibyte character sequences (Tatsuo)

     ----------------------------------------------------------------------

  PL/pgSQL

   Now uses portals for SELECT loops, allowing huge result sets (Jan)
   CURSOR and REFCURSOR support (Jan)
   Can now return open cursors (Jan)
   Add ELSEIF (Klaus Reger)
   Improve PL/pgSQL error reporting, including location of error (Tom)
   Allow IS or FOR key words in cursor declaration, for compatibility (Bruce)
   Fix for SELECT ... FOR UPDATE (Tom)
   Fix for PERFORM returning multiple rows (Tom)
   Make PL/pgSQL use the server's type coercion code (Tom)
   Memory leak fix (Jan, Tom)
   Make trailing semicolon optional (Tom)

     ----------------------------------------------------------------------

  PL/Perl

   New untrusted PL/Perl (Alex Pilosov)
   PL/Perl is now built on some platforms even if libperl is not shared (Peter E)

     ----------------------------------------------------------------------

  PL/Tcl

   Now reports errorInfo (Vsevolod Lobko)
   Add spi_lastoid function (bob@redivi.com)

     ----------------------------------------------------------------------

  PL/Python

   ...is new (Andrew Bosma)

     ----------------------------------------------------------------------

  Psql

   \d displays indexes in unique, primary groupings (Christopher Kings-Lynne)
   Allow trailing semicolons in backslash commands (Greg Sabino Mullane)
   Read password from /dev/tty if possible
   Force new password prompt when changing user and database (Tatsuo, Tom)
   Format the correct number of columns for Unicode (Patrice)

     ----------------------------------------------------------------------

  Libpq

   New function PQescapeString() to escape quotes in command strings (Florian Weimer)
   New function PQescapeBytea() escapes binary strings for use as SQL string literals

     ----------------------------------------------------------------------

  JDBC

   Return OID of INSERT (Ken K)
   Handle more data types (Ken K)
   Handle single quotes and newlines in strings (Ken K)
   Handle NULL variables (Ken K)
   Fix for time zone handling (Barry Lind)
   Improved Druid support
   Allow eight-bit characters with non-multibyte server (Barry Lind)
   Support BIT, BINARY types (Ned Wolpert)
   Reduce memory usage (Michael Stephens, Dave Cramer)
   Update DatabaseMetaData (Peter E)
   Add DatabaseMetaData.getCatalogs() (Peter E)
   Encoding fixes (Anders Bengtsson)
   Get/setCatalog methods (Jason Davies)
   DatabaseMetaData.getColumns() now returns column defaults (Jason Davies)
   DatabaseMetaData.getColumns() performance improvement (Jeroen van Vianen)
   Some JDBC1 and JDBC2 merging (Anders Bengtsson)
   Transaction performance improvements (Barry Lind)
   Array fixes (Greg Zoller)
   Serialize addition 
   Fix batch processing (Rene Pijlman)
   ExecSQL method reorganization (Anders Bengtsson)
   GetColumn() fixes (Jeroen van Vianen)
   Fix isWriteable() function (Rene Pijlman)
   Improved passage of JDBC2 conformance tests (Rene Pijlman)
   Add bytea type capability (Barry Lind)
   Add isNullable() (Rene Pijlman)
   JDBC date/time test suite fixes (Liam Stewart)
   Fix for SELECT 'id' AS xxx FROM table (Dave Cramer)
   Fix DatabaseMetaData to show precision properly (Mark Lillywhite)
   New getImported/getExported keys (Jason Davies)
   MD5 password encryption support (Jeremy Wohl)
   Fix to actually use type cache (Ned Wolpert)

     ----------------------------------------------------------------------

  ODBC

   Remove query size limit (Hiroshi)
   Remove text field size limit (Hiroshi)
   Fix for SQLPrimaryKeys in multibyte mode (Hiroshi)
   Allow ODBC procedure calls (Hiroshi)
   Improve boolean handing (Aidan Mountford)
   Most configuration options on setable via DSN (Hiroshi)
   Multibyte, performance fixes (Hiroshi)
   Allow driver to be used with iODBC or unixODBC (Peter E)
   MD5 password encryption support (Bruce)
   Add more compatibility functions to odbc.sql (Peter E)

     ----------------------------------------------------------------------

  ECPG

   EXECUTE ... INTO implemented (Christof Petig)
   Multiple row descriptor support (e.g. CARDINALITY) (Christof Petig)
   Fix for GRANT parameters (Lee Kindness)
   Fix INITIALLY DEFERRED bug
   Various bug fixes (Michael, Christof Petig)
   Auto allocation for indicator variable arrays (int *ind_p=NULL)
   Auto allocation for string arrays (char **foo_pp=NULL)
   ECPGfree_auto_mem fixed
   All function names with external linkage are now prefixed by ECPG
   Fixes for arrays of structures (Michael)

     ----------------------------------------------------------------------

  Misc. Interfaces

   Python fix fetchone() (Gerhard Haring)
   Use UTF, Unicode in Tcl where appropriate (Vsevolod Lobko, Reinhard Max)
   Add Tcl COPY TO/FROM (ljb)
   Prevent output of default index op class in pg_dump (Tom)
   Fix libpgeasy memory leak (Bruce)

     ----------------------------------------------------------------------

  Build and Install

   Configure, dynamic loader, and shared library fixes (Peter E)
   Fixes in QNX 4 port (Bernd Tegge)
   Fixes in Cygwin and Win32 ports (Jason Tishler, Gerhard Haring, Dmitry Yurtaev, Darko Prenosil, Mikhail Terekhov)
   Fix for Win32 socket communication failures (Magnus, Mikhail Terekhov)
   Hurd compile fix (Oliver Elphick)
   BeOS fixes (Cyril Velter)
   Remove configure --enable-unicode-conversion, now enabled by multibyte (Tatsuo)
   AIX fixes (Tatsuo, Andreas)
   Fix parallel make (Peter E)
   Install SQL language manual pages into OS-specific directories (Peter E)
   Rename config.h to pg_config.h (Peter E)
   Reorganize installation layout of header files (Peter E)

     ----------------------------------------------------------------------

  Source Code

   Remove SEP_CHAR (Bruce)
   New GUC hooks (Tom)
   Merge GUC and command line handling (Marko Kreen)
   Remove EXTEND INDEX (Martijn van Oosterhout, Tom)
   New pgjindent utility to indent java code (Bruce)
   Remove define of true/false when compiling under C++ (Leandro Fanzone, Tom)
   pgindent fixes (Bruce, Tom)