- "http://gborg.postgresql.org">.
-
-
-
-
- The server now uses its own time zone database, rather than the
- one supplied by the operating system. This will provide consistent
- behavior across all platforms. In most cases, there should be
- little noticeable difference in time zone behavior, except that
- the time zone names used by SET/SHOW
- TimeZone may
- be different from what your platform provides.
-
-
-
-
-
Configure's threading option no longer requires- users to run tests or edit configuration files; threading options
- are now detected automatically.
-
-
-
-
- Now that tablespaces have been implemented,
-
initlocation has been removed.-
-
-
-
- The API for user-defined GiST indexes has been changed. The
- Union and PickSplit methods are now passed a pointer to a
- special GistEntryVector structure,
- rather than a bytea.
-
-
-
-
-
-
-
-
Deprecated Features
-
- Some aspects of
PostgreSQL's behavior
- have been determined to be suboptimal. For the sake of backward
- compatibility these have not been removed in 8.0, but they are
- considered deprecated and will be removed in the next major
- release.
+
+
+
+
Changes
+
+ Below you will find a detailed account of the changes between
+ release 8.0 and the previous major release.
-
-
-
- The 8.1 release will remove the to_char() function
- for intervals.
-
-
-
-
- The server now warns of empty strings passed to
- oid/float4/float8 data
- types, but continues to interpret them as zeroes as before.
- In the next major release, empty strings will be considered
- invalid input for these data types.
-
-
-
-
- By default, tables in
PostgreSQL 8.0
- and earlier are created with OIDs. In the next release,
- this will not be the case: to create a table
- that contains OIDs, the
- be specified or the default_with_oids
- configuration parameter must be set. Users are encouraged to
- explicitly specify
- require OIDs for compatibility with future releases of
-
-
-
-
-
-
-
Changes
-
- Below you will find a detailed account of the changes between
- release 8.0 and the previous major release.
-
-
-
-
Performance Improvements
-
-
-
- Support cross-data-type index usage (Tom)
-
- Before this change, many queries would not use an index if the data
- types did not match exactly. This improvement makes index usage more
- intuitive and consistent.
-
-
-
-
- New buffer replacement strategy that improves caching (Jan)
-
- Prior releases used a least-recently-used (LRU) cache to keep
- recently referenced pages in memory. The LRU algorithm
- did not consider the number of times a specific cache entry was
- accessed, so large table scans could force out useful cache pages.
- The new cache algorithm uses four separate lists to track most
- recently used and most frequently used cache pages and dynamically
- optimize their replacement based on the work load. This should
- lead to much more efficient use of the shared buffer cache.
- Administrators who have tested shared buffer sizes in the past
- should retest with this new cache replacement policy.
-
-
-
-
- Add subprocess to write dirty buffers periodically to reduce
- checkpoint writes (Jan)
-
- In previous releases, the checkpoint process, which runs every few
- minutes, would write all dirty buffers to the operating system's
- buffer cache then flush all dirty operating system buffers to
- disk. This resulted in a periodic spike in disk usage that often
- hurt performance. The new code uses a background writer to trickle
- disk writes at a steady pace so checkpoints have far fewer dirty
- pages to write to disk. Also, the new code does not issue a global
- sync() call, but instead fsync()s just
- the files written since the last checkpoint. This should improve
- performance and minimize degradation during checkpoints.
-
-
-
-
- Add ability to prolong vacuum to reduce performance impact (Jan)
-
- On busy systems, VACUUM performs many I/O
- requests which can hurt performance for other users. This
- release allows you to slow down VACUUM to
- reduce its impact on other users, though this increases the
- total duration of VACUUM.
-
-
-
-
- Improve B-tree index performance for duplicate keys (Dmitry Tkach, Tom)
-
- This improves the way indexes are scanned when many duplicate
- values exist in the index.
-
-
-
-
- Use dynamically-generated table size estimates while planning (Tom)
-
- Formerly the planner estimated table sizes using the values seen
- by the last VACUUM or ANALYZE,
- both as to physical table size (number of pages) and number of rows.
- Now, the current physical table size is obtained from the kernel,
- and the number of rows is estimated by multiplying the table size
- by the row density (rows per page) seen by the last
- VACUUM or ANALYZE. This should
- produce more reliable estimates in cases where the table size has
- changed significantly since the last housekeeping command.
-
-
-
-
- Improved index usage with OR clauses (Tom)
-
- This allows the optimizer to use indexes in statements with many OR
- clauses that would not have been indexed in the past. It can also use
- multi-column indexes where the first column is specified and the second
- column is part of an OR clause.
-
-
-
-
- Improve matching of partial index clauses (Tom)
-
- The server is now smarter about using partial indexes in queries
- involving complex
-
-
-
-
- Improve performance of the GEQO optimizer (Tom)
-
- The GEQO optimizer is used to plan queries involving many tables (by
- default, twelve or more). This release speeds up the way queries are
- analyzed to decrease time spent in optimization.
-
-
-
-
- Miscellaneous optimizer improvements
-
- There is not room here to list all the minor improvements made, but
- numerous special cases work better than in prior releases.
-
-
-
-
- Improve lookup speed for C functions (Tom)
-
- This release uses a hash table to lookup information for dynamically
- loaded C functions. This improves their speed so they perform nearly as
- quickly as functions that are built into the server executable.
-
-
-
-
- Add type-specific ANALYZE statistics
- capability (Mark Cave-Ayland)
-
- This feature allows more flexibility in generating statistics
- for non-standard data types.
-
-
-
-
- ANALYZE now collects statistics for
- expression indexes (Tom)
-
- Expression indexes (also called functional indexes) allow users to
- index not just columns but the results of expressions and function
- calls. With this release, the optimizer can gather and use statistics
- about the contents of expression indexes. This will greatly improve
- the quality of planning for queries in which an expression index is
- relevant.
-
-
-
-
- New two-stage sampling method for ANALYZE
- (Manfred Koizar)
-
- This gives better statistics when the density of valid rows is very
- different in different regions of a table.
-
-
-
-
- Speed up TRUNCATE (Tom)
-
- This buys back some of the performance loss observed in 7.4, while still
- keeping TRUNCATE transaction-safe.
-
-
-
-
-
-
-
-
-
Server Changes
-
-
-
- Add WAL file archiving and point-in-time recovery (Simon Riggs)
-
-
-
-
- Add tablespaces so admins can control disk layout (Gavin)
-
-
-
-
- Add a built-in log rotation program (Andreas Pflug)
-
- It is now possible to log server messages conveniently without
- relying on either
syslog or an external log- rotation program.
-
-
-
-
- Add new read-only server configuration parameters to show server
- compile-time settings: block_size,
- integer_datetimes, max_function_args,
- max_identifier_length, max_index_keys (Joe)
-
-
-
-
- Make quoting of sameuser, samegroup, and
- all remove special meaning of these terms in
- pg_hba.conf (Andrew)
-
-
-
-
- Use clearer IPv6 name ::1/128 for
- localhost in default pg_hba.conf (Andrew)
-
-
-
-
- Use CIDR format in pg_hba.conf examples (Andrew)
-
-
-
-
- Rename server configuration parameters SortMem and
- VacuumMem to work_mem and
- maintenance_work_mem (Old names still supported) (Tom)
-
- This change was made to clarify that bulk operations such as index and
- foreign key creation use maintenance_work_mem, while
- work_mem is for workspaces used during query execution.
-
-
-
-
- Allow logging of session disconnections using server configuration
- log_disconnections (Andrew)
-
-
-
-
- Add new server configuration parameter log_line_prefix to
- allow control of information emitted in each log line (Andrew)
-
- Available information includes user name, database name, remote IP
- address, and session start time.
-
-
-
-
- Remove server configuration parameters log_pid,
- log_timestamp, log_source_port; functionality
- superseded by log_line_prefix (Andrew)
-
-
-
-
- Replace the virtual_host and tcpip_socket
- parameters with a unified listen_addresses parameter
- (Andrew, Tom)
-
- virtual_host could only specify a single IP address to
- listen on. listen_addresses allows multiple addresses
- to be specified.
-
-
-
-
- Listen on localhost by default, which eliminates the need for the
-
-
- Listening on localhost (127.0.0.1) opens no new
- security holes but allows configurations like Windows and JDBC,
- which do not support local sockets, to work without special
- adjustments.
-
-
-
-
- Remove syslog server configuration parameter, and add more
- logical log_destination variable to control log output
- location (Magnus)
-
-
-
-
- Change server configuration parameter log_statement to take
- values all, mod, ddl, or
- none to select which queries are logged (Bruce)
-
- This allows administrators to log only data definition changes or
- only data modification statements.
-
-
-
-
- Some logging-related configuration parameters could formerly be adjusted
- by ordinary users, but only in the more verbose direction.
- They are now treated more strictly: only superusers can set them.
- However, a superuser may use ALTER USER to provide per-user
- settings of these values for non-superusers. Also, it is now possible
- for superusers to set values of superuser-only configuration parameters
- via PGOPTIONS.
-
-
-
-
- Allow configuration files to be placed outside the data directory (mlw)
-
- By default, configuration files are kept in the cluster's top directory.
- With this addition, configuration files can be placed outside the
- data directory, easing administration.
-
-
-
-
- Plan prepared queries only when first executed so constants can be
- used for statistics (Oliver Jowett)
-
- Prepared statements plan queries once and execute them many
- times. While prepared queries avoid the overhead of re-planning
- on each use, the quality of the plan suffers from not knowing the exact
- parameters to be used in the query. In this release, planning of
- unnamed prepared statements is delayed until the first execution,
- and the actual parameter values of that execution are used as
- optimization hints. This allows use of out-of-line parameter passing
- without incurring a performance penalty.
-
-
-
-
- Allow DECLARE CURSOR to take parameters
- (Oliver Jowett)
-
- It is now useful to issue DECLARE CURSOR in a
- Parse message with parameters. The parameter values
- sent at Bind time will be substituted into the
- execution of the cursor's query.
-
-
-
-
- Fix hash joins and aggregates of inet and
- cidr data types (Tom)
-
- Release 7.4 handled hashing of mixed inet and
- cidr values incorrectly. (This bug did not exist
- in prior releases because they wouldn't try to hash either
- data type.)
-
-
-
-
- Make log_duration print only when log_statement
- prints the query (Ed L.)
-
-
-
-
-
-
-
-
-
Query Changes
-
-
-
- Add savepoints (nested transactions) (Alvaro)
-
-
-
-
- Unsupported isolation levels are now accepted and promoted to the
- nearest supported level (Peter)
-
- The SQL specification states that if a database doesn't support a
- specific isolation level, it should use the next more restrictive level.
- This change complies with that recommendation.
-
-
-
-
- Allow BEGIN WORK to specify transaction
- isolation levels like START TRANSACTION does
- (Bruce)
-
-
-
-
- Fix table permission checking for cases in which rules generate
- a query type different from the originally submitted query (Tom)
-
-
-
-
- Implement dollar quoting to simplify single-quote usage (Andrew, Tom,
- David Fetter)
-
- In previous releases, because single quotes had to be used to
- quote a function's body, the use of single quotes inside the
- function text required use of two single quotes or other error-prone
- notations. With this release we add the ability to use "dollar
- quoting" to quote a block of text. The ability to use different
- quoting delimiters at different nesting levels greatly simplifies
- the task of quoting correctly, especially in complex functions.
- Dollar quoting can be used anywhere quoted text is needed.
-
-
-
-
- Make CASE val WHEN compval1 THEN ... evaluate val only once (Tom)
-
-
- times. This has benefits when the expression is complex or is
- volatile.
-
-
-
-
- Test
- aggregate query (Tom)
-
- Fixes improper failure of cases such as SELECT SUM(win)/SUM(lose)
- ... GROUP BY ... HAVING SUM(lose) > 0. This should work but formerly
- could fail with divide-by-zero.
-
-
-
-
- Replace max_expr_depth parameter with
- max_stack_depth parameter, measured in kilobytes of stack
- size (Tom)
-
- This gives us a fairly bulletproof defense against crashing due to
- runaway recursive functions. Instead of measuring the depth of expression
- nesting, we now directly measure the size of the execution stack.
-
-
-
-
- Allow arbitrary row expressions (Tom)
-
- This release allows SQL expressions to contain arbitrary composite
- types, that is, row values. It also allows functions to more easily
- take rows as arguments and return row values.
-
-
-
-
- Allow
- in row and subselect comparisons (Fabien Coelho)
-
-
-
-
- Avoid locale-specific case conversion of basic ASCII letters in
- identifiers and keywords (Tom)
-
- This solves the Turkish problem with mangling of words
- containing I and i. Folding of characters
- outside the 7-bit-ASCII set is still locale-aware.
-
-
-
-
- Improve syntax error reporting (Fabien, Tom)
-
- Syntax error reports are more useful than before.
-
-
-
-
- Change EXECUTE to return a completion tag
- matching the executed statement (Kris Jurka)
-
- Previous releases return an EXECUTE tag for
- any EXECUTE call. In this release, the tag
- returned will reflect the command executed.
-
-
-
-
- Avoid emitting
-
- Such a clause makes no logical sense, but in some cases the rule
- decompiler formerly produced this syntax.
-
-
-
-
-
-
-
-
-
Object Manipulation Changes
-
-
-
- Add COMMENT ON for casts, conversions, languages,
- operator classes, and large objects (Christopher)
-
-
-
-
- Add new server configuration parameter default_with_oids to
- control whether tables are created with OIDs by default (Neil)
-
- This allows administrators to control whether CREATE
- TABLE commands create tables with or without OID
- columns by default. (Note: the current factory default setting for
- default_with_oids is TRUE, but the default
- will become FALSE in future releases.)
-
-
-
-
- Add
- CREATE TABLE AS (Neil)
-
-
-
-
- Allow ALTER TABLE DROP COLUMN to drop an OID
- column (ALTER TABLE SET WITHOUT OIDS still works)
- (Tom)
-
-
-
-
- Allow composite types as table columns (Tom)
-
-
-
-
- Allow ALTER ... ADD COLUMN with defaults and
-
-
- It is now possible for
- that is not initially filled with NULLs, but with a specified
- default value.
-
-
-
-
- Add ALTER COLUMN TYPE to change column's type (Rod)
-
- It is now possible to alter a column's data type without dropping
- and re-adding the column.
-
-
-
-
- Allow multiple ALTER actions in a single ALTER
- TABLE command (Rod)
-
- This is particularly useful for ALTER commands that
- rewrite the table (which include
-
- ALTER commands together, the table need be rewritten
- only once.
-
-
-
-
- Allow ALTER TABLE to add SERIAL
- columns (Tom)
-
- This falls out from the new capability of specifying defaults for new
- columns.
-
-
-
-
- Allow changing the owners of aggregates, conversions, databases,
- functions, operators, operator classes, schemas, types, and tablespaces
- (Christopher, Euler Taveira de Oliveira)
-
- Previously this required modifying the system tables directly.
-
-
-
-
- Allow temporary object creation to be limited to
- DEFINER functions (Sean Chittenden)
-
-
-
-
- Add
-
- Prior to this release, there was no way to clear an auto-cluster
- specification except to modify the system tables.
-
-
-
-
- Constraint/Index/SERIAL names are now
- table_column_type
- with numbers appended to guarantee uniqueness within the schema
- (Tom)
-
- The SQL specification states that such names should be unique
- within a schema.
-
-
-
-
- Add pg_get_serial_sequence() to return a
- SERIAL column's sequence name (Christopher)
-
- This allows automated scripts to reliably find the SERIAL
- sequence name.
-
-
-
-
- Warn when primary/foreign key data type mismatch requires costly lookup
-
-
-
-
- New ALTER INDEX command to allow moving of indexes
- between tablespaces (Gavin)
-
-
-
-
- Make ALTER TABLE OWNER change dependent sequence
- ownership too (Alvaro)
-
-
-
-
-
-
-
-
-
-
Utility Command Changes
-
-
-
- Allow CREATE SCHEMA to create triggers,
- indexes, and sequences (Neil)
-
-
-
-
- Add
- Coelho)
-
- This allows
-
-
-
-
-
- Add
-
- This allows the LOCK command to fail if it
- would have to wait for the requested lock.
-
-
-
-
- Allow COPY to read and write
- comma-separated-value (CSV) files (Andrew, Bruce)
-
-
-
-
- Generate error if the COPY delimiter and NULL
- string conflict (Bruce)
-
-
-
-
- GRANT/REVOKE behavior
- follows the SQL spec more closely
-
-
-
-
- Avoid locking conflict between CREATE INDEX
- and CHECKPOINT (Tom)
-
- In 7.3 and 7.4, a long-running B-tree index build could block concurrent
- CHECKPOINTs from completing, thereby causing WAL bloat because the
- WAL log could not be recycled.
-
-
-
-
- Database-wide ANALYZE does not hold locks
- across tables (Tom)
-
- This reduces the potential for deadlocks against other backends
- that want exclusive locks on tables. To get the benefit of this
- change, do not execute database-wide ANALYZE
- inside a transaction block (BEGIN block); it
- must be able to commit and start a new transaction for each
- table.
-
-
-
-
- REINDEX does not exclusively lock the index's
- parent table anymore
-
- The index itself is still exclusively locked, but readers of the
- table can continue if they are not using the particular index
- being rebuilt.
-
-
-
-
- Erase MD5 user passwords when a user is renamed (Bruce)
-
-
PostgreSQL uses the user name as salt
- when encrypting passwords via MD5. When a user's name is changed,
- the salt will no longer match the stored MD5 password, so the
- stored password becomes useless. In this release a notice is
- generated and the password is cleared. A new password must then
- be assigned if the user is to be able to log in with a password.
-
-
-
-
- New
pg_ctl -
- Windows does not have a kill command to send signals to
- backends so this capability was added to
pg_ctl.-
-
-
-
- Information schema improvements
-
-
-
-
- Add
-
initdb so the initial password can be
- set by GUI tools (Magnus)
-
-
-
-
- Detect locale/encoding mismatch in
-
-
-
-
- Add
- register Windows operating system service (Dave Page)
-
-
-
-
-
-
-
-
-
Data Type and Function Changes
-
-
-
- More complete support for composite types (row types) (Tom)
-
- Composite values can be used in many places where only scalar values
- worked before.
-
-
-
-
- Reject non-rectangular array values as erroneous (Joe)
-
- Formerly, array_in would silently build a
- surprising result.
-
-
-
-
- Overflow in integer arithmetic operations is now detected (Tom)
-
-
-
-
- The arithmetic operators associated with the single-byte
- "char" data type have been removed.
-
- Formerly, the parser would select these operators in many situations
- where an unable to select an operator error would be more
- appropriate, such as null * null. If you actually want
- to do arithmetic on a "char" column, you can cast it to
- integer explicitly.
-
-
-
-
- Syntax checking of array input values considerably tightened up (Joe)
-
- Junk that was previously allowed in odd places with odd results
- now causes an ERROR, for example, non-whitespace
- after the closing right brace.
-
-
-
-
- Empty-string array element values must now be written as
- "", rather than writing nothing (Joe)
-
- Formerly, both ways of writing an empty-string element value were
- allowed, but now a quoted empty string is required. The case where
- nothing at all appears will probably be considered to be a NULL
- element value in some future release.
-
-
-
-
- Array element trailing whitespace is now ignored (Joe)
-
- Formerly leading whitespace was ignored, but trailing whitespace
- between an element value and the delimiter or right brace was
- significant. Now trailing whitespace is also ignored.
-
-
-
-
- Emit array values with explicit array bounds when lower bound is not one
- (Joe)
-
-
-
-
- Accept YYYY-monthname-DD as a date string (Tom)
-
-
-
-
- Make netmask and hostmask functions
- return maximum-length mask length (Tom)
-
-
-
-
- Change factorial function to return numeric (Gavin)
-
- Returning numeric allows the factorial function to
- work for a wider range of input values.
-
-
-
-
- to_char/to_date() date conversion
- improvements (Kurt Roeckx, Fabien Coelho)
-
-
-
-
- Make length() disregard trailing spaces in
- CHAR(n) (Gavin)
-
- This change was made to improve consistency: trailing spaces are
- semantically insignificant in CHAR(n) data, so they
- should not be counted by length().
-
-
-
-
- Warn about empty string being passed to
- OID/float4/float8 data types (Neil)
-
- 8.1 will throw an error instead.
-
-
-
-
- Allow leading or trailing whitespace in
- int2/int4/int8/float4/float8
- input routines
- (Neil)
-
-
-
-
- Better support for IEEE Infinity and NaN
- values in float4/float8 (Neil)
-
- These should now work on all platforms that support IEEE-compliant
- floating point arithmetic.
-
-
-
-
- Add
-
-
-
-
- Fix to_char for 1 BC
- (previously it returned 1 AD) (Bruce)
-
-
-
-
- Fix date_part(year) for BC dates (previously it
- returned one less than the correct year) (Bruce)
-
-
-
-
- Fix date_part() to return the proper millennium and
- century (Fabien Coelho)
-
- In previous versions, the century and millennium results had a wrong
- number and started in the wrong year, as compared to standard
- reckoning of such things.
-
-
-
-
- Add ceiling() as an alias for ceil(),
- and power() as an alias for pow() for
- standards compliance (Neil)
-
-
-
-
- Change ln(), log(),
- power(), and sqrt() to emit the correct
- SQLSTATE error codes for certain error conditions, as
- specified by SQL:2003 (Neil)
-
-
-
-
- Add width_bucket() function as defined by SQL:2003 (Neil)
-
-
-
-
- Add generate_series() functions to simplify working
- with numeric sets (Joe)
-
-
-
-
- Fix upper/lower/initcap() functions to work with
- multibyte encodings (Tom)
-
-
-
-
- Add boolean and bitwise integer
- aggregates (Fabien Coelho)
-
-
-
-
- New session information functions to return network addresses for client
- and server (Sean Chittenden)
-
-
-
-
- Add function to determine the area of a closed path (Sean Chittenden)
-
-
-
-
- Add function to send cancel request to other backends (Magnus)
-
-
-
-
- Add interval plus datetime operators (Tom)
-
- The reverse ordering, datetime plus interval,
- was already supported, but both are required by the SQL standard.
-
-
-
-
- Casting an integer to BIT(N) selects the rightmost N bits
- of the integer
- (Tom)
-
- In prior releases, the leftmost N bits were selected, but this was
- deemed unhelpful, not to mention inconsistent with casting from bit
- to int.
-
-
-
-
- Require CIDR values to have all non-masked bits be zero
- (Kevin Brintnall)
-
-
-
-
-
-
-
-
-
Server-Side Language Changes
-
-
-
- In READ COMMITTED serialization mode, volatile functions
- now see the results of concurrent transactions committed up to the
- beginning of each statement within the function, rather than up to the
- beginning of the interactive command that called the function.
-
-
-
-
- Functions declared STABLE or IMMUTABLE always
- use the snapshot of the calling query, and therefore do not see the
- effects of actions taken after the calling query starts, whether in
- their own transaction or other transactions. Such a function must be
- read-only, too, meaning that it cannot use any SQL commands other than
- SELECT. There is a considerable performance gain from
- declaring a function STABLE or IMMUTABLE
- rather than VOLATILE.
-
-
-
-
- Non-deferred
- after completion of the triggering query, rather than upon
- finishing the current interactive command. This makes a difference
- when the triggering query occurred within a function: the trigger
- is invoked before the function proceeds to its next operation. For
- example, if a function inserts a new row into a table, any
- non-deferred foreign key checks occur before proceeding with the
- function.
-
-
-
-
- Allow function parameters to be declared with names (Dennis Bjorklund)
-
- This allows better documentation of functions. Whether the names
- actually do anything depends on the specific function language
- being used.
-
-
-
-
- Allow PL/pgSQL parameter names to be referenced in the function (Dennis Bjorklund)
-
- This basically creates an automatic alias for each named parameter.
-
-
-
-
- Do minimal syntax checking of PL/pgSQL functions at creation time (Tom)
-
- This allows us to catch simple syntax errors sooner.
-
-
-
-
- More support for composite types (row and record variables) in PL/pgSQL
-
- For example, it now works to pass a rowtype variable to another function
- as a single variable.
-
-
-
-
- Default values for PL/pgSQL variables can now reference previously
- declared variables
-
-
-
-
- Improve parsing of PL/pgSQL FOR loops (Tom)
-
- Parsing is now driven by presence of ".." rather than
- data type of
- correct functions, but should result in more understandable error
- messages when a mistake is made.
-
-
-
-
- Major overhaul of PL/Perl server-side language (Command Prompt, Andrew Dunstan)
-
-
-
-
- In PL/Tcl, SPI commands are now run in subtransactions. If an error
- occurs, the subtransaction is cleaned up and the error is reported
- as an ordinary Tcl error, which can be trapped with catch.
- Formerly, it was not possible to catch such errors.
-
-
-
-
- Accept ELSEIF in PL/pgSQL (Neil)
-
- Previously PL/pgSQL only allowed ELSIF, but many people
- are accustomed to spelling this keyword ELSEIF.
-
-
-
-
-
-
-
-
-
<application>psql</> Changes
-
-
-
- Improve
psql information display about database- objects (Christopher)
-
-
-
-
- Allow
psql to display group membership in- \du and \dg (Markus Bertheau)
-
-
-
-
- Prevent
psql \dn from showing- temporary schemas (Bruce)
-
-
-
-
- Allow
psql to handle tilde user expansion for file- names (Zach Irmen)
-
-
-
-
- Allow
psql to display fancy prompts, including- color, via
readline (Reece Hart, Chet Ramey)-
-
-
-
- Make
psql \copy match COPY command syntax- fully (Tom)
-
-
-
-
- Show the location of syntax errors (Fabien Coelho, Tom)
-
-
-
-
- Add
CLUSTER information to
psql- \d display
- (Bruce)
-
-
-
-
- Change
psql \copy stdin/stdout to read- from command input/output (Bruce)
-
-
-
-
- Add
-
psql's stdin/stdout (Mark- Feit)
-
-
-
-
- Add global
psql configuration file, psqlrc.sample- (Bruce)
-
- This allows a central file where global
psql startup commands can- be stored.
-
-
-
-
- Have
psql \d+ indicate if the table- has an OID column (Neil)
-
-
-
-
- On Windows, use binary mode in
psql when reading files so control-Z- is not seen as end-of-file
-
-
-
-
- Have \dn+ show permissions and description for schemas (Dennis
- Bjorklund)
-
-
-
-
- Improve tab completion support (Stefan Kaltenbrunn, Greg Sabino Mullane)
-
-
-
-
- Allow boolean settings to be set using upper or lower case (Michael Paesold)
-
-
-
-
-
-
-
-
-
<application>pg_dump</> Changes
-
-
-
- Use dependency information to improve the reliability of
-
- This should solve the longstanding problems with related objects
- sometimes being dumped in the wrong order.
-
-
-
-
- Have
pg_dump output objects in alphabetical order if possible (Tom)-
- This should make it easier to identify changes between
- dump files.
-
-
-
-
- Allow
pg_restore to ignore some SQL errors (Fabien Coelho)-
- This makes
pg_restore's behavior similar to the- results of feeding a
pg_dump output script to-
psql. In most cases, ignoring errors and plowing- ahead is the most useful thing to do. Also added was a pg_restore
- option to give the old behavior of exiting on an error.
-
-
-
-
-
pg_restore - objects' schema names
-
-
-
-
- New begin/end markers in
pg_dump text output (Bruce)-
-
-
-
- Add start/stop times for
-
pg_dump/pg_dumpall in verbose mode- (Bruce)
-
-
-
-
- Allow most
pg_dump options in-
pg_dumpall (Christopher)-
-
-
-
- Have
pg_dump use ALTER OWNER rather- than SET SESSION AUTHORIZATION by default
- (Christopher)
-
-
-
-
-
-
-
-
-
libpq Changes
-
-
-
- Make libpq's
-
-
-
-
- Add PQmbdsplen() which returns the display length
- of a character (Tatsuo)
-
-
-
-
- Add thread locking to
SSL and-
Kerberos connections (Manfred Spraul)-
-
-
-
- Allow PQoidValue(), PQcmdTuples(), and
- PQoidStatus() to work on EXECUTE
- commands (Neil)
-
-
-
-
- Add PQserverVersion() to provide more convenient
- access to the server version number (Greg Sabino Mullane)
-
-
-
-
- Add PQprepare/PQsendPrepared() functions to support
- preparing statements without necessarily specifying the data types
- of their parameters (Abhijit Menon-Sen)
-
-
-
-
- Many ECPG improvements, including SET DESCRIPTOR (Michael)
-
-
-
-
-
-
-
-
-
Source Code Changes
-
-
-
- Allow the database server to run natively on Windows (Claudio, Magnus, Andrew)
-
-
-
-
- Shell script commands converted to C versions for Windows support (Andrew)
-
-
-
-
- Create an extension makefile framework (Fabien Coelho, Peter)
-
- This simplifies the task of building extensions outside the original
- source tree.
-
-
-
-
- Support relocatable installations (Bruce)
-
- Directory paths for installed files (such as the
- /share directory) are now computed relative to the
- actual location of the executables, so that an installation tree
- can be moved to another place without reconfiguring and
- rebuilding.
-
-
-
-
- Use
- allow
-
-
-
-
- Add
-
-
-
-
- Upgrade to
DocBook V4.2 SGML (Peter)-
-
-
-
- New
PostgreSQL CVS tag (Marc)-
- This was done to make it easier for organizations to manage their
- own copies of the
PostgreSQL-
CVS repository. File version stamps from the master- repository will not get munged by checking into or out of a copied
- repository.
-
-
-
-
- Clarify locking code (Manfred Koizar)
-
-
-
-
- Buffer manager cleanup (Neil)
-
-
-
-
- Decouple platform tests from CPU spinlock code (Bruce, Tom)
-
-
-
-
- Add inlined test-and-set code on PA-RISC for
gcc- (ViSolve, Tom)
-
-
-
-
- Improve i386 spinlock code (Manfred Spraul)
-
-
-
-
- Clean up spinlock assembly code to avoid warnings from newer
-
-
-
-
- Remove JDBC from source tree; now a separate project
-
-
-
-
- Remove the libpgtcl client interface; now a separate project
-
-
-
-
- More accurately estimate memory and file descriptor usage (Tom)
-
-
-
-
- Improvements to the Mac OS X startup scripts (Ray A.)
-
-
-
-
- New fsync() test program (Bruce)
-
-
-
-
- Major documentation improvements (Neil, Peter)
-
-
-
-
- Remove
pg_encoding; not needed
- anymore
-
-
-
-
- Remove
pg_id; not needed anymore
-
-
-
-
- Remove
initlocation; not needed
- anymore
-
-
-
-
- Auto-detect thread flags (no more manual testing) (Bruce)
-
-
-
-
- Use Olson's public domain
timezone library (Magnus)-
-
-
-
- With threading enabled, use thread flags on Unixware for
- backend executables too (Bruce)
-
- Unixware cannot mix threaded and non-threaded object files in the
- same executable, so everything must be compiled as threaded.
-
-
-
-
-
psql now uses a flex-generated- lexical analyzer to process command strings
-
-
-
-
- Reimplement the linked list data structure used throughout the
- backend (Neil)
-
- This improves performance by allowing list append and length
- operations to be more efficient.
-
-
-
-
- Allow dynamically loaded modules to create their own server configuration
- parameters (Thomas Hallgren)
-
-
-
-
- New Brazilian version of FAQ (Euler Taveira de Oliveira)
-
-
-
-
- Add French FAQ (Guillaume Lelarge)
-
-
-
-
- New
pgevent for Windows logging-
-
-
-
- Make libpq and ECPG build as proper shared libraries on OS X (Tom)
-
-
-
-
-
-
-
-
-
Contrib Changes
-
-
-
- Overhaul of contrib/dblink (Joe)
-
-
-
-
- contrib/dbmirror improvements (Steven Singer)
-
-
-
-
- New contrib/xml2 (John Gray, Torchbox)
-
-
-
-
- Updated contrib/mysql
-
-
-
-
- New version of contrib/btree_gist (Teodor)
-
-
-
-
- New contrib/trgm, trigram matching for
-
-
-
-
- Many contrib/tsearch2 improvements (Teodor)
-
-
-
-
- Add double metaphone to contrib/fuzzystrmatch (Andrew)
-
-
-
-
- Allow contrib/pg_autovacuum to run as a Windows service (Dave Page)
-
-
-
-
- Add functions to contrib/dbsize (Andreas Pflug)
-
-
-
-
- Removed contrib/pg_logger: obsoleted by integrated logging
- subprocess
-
-
-
-
- Removed contrib/rserv: obsoleted by various separate projects
-
-
-
-
-
-
-
-
-
+
+
+
Performance Improvements
+
+
+
+ Support cross-data-type index usage (Tom)
+
+ Before this change, many queries would not use an index if the data
+ types did not match exactly. This improvement makes index usage more
+ intuitive and consistent.
+
+
+
+
+ New buffer replacement strategy that improves caching (Jan)
+
+ Prior releases used a least-recently-used (LRU) cache to keep
+ recently referenced pages in memory. The LRU algorithm
+ did not consider the number of times a specific cache entry was
+ accessed, so large table scans could force out useful cache pages.
+ The new cache algorithm uses four separate lists to track most
+ recently used and most frequently used cache pages and dynamically
+ optimize their replacement based on the work load. This should
+ lead to much more efficient use of the shared buffer cache.
+ Administrators who have tested shared buffer sizes in the past
+ should retest with this new cache replacement policy.
+
+
+
+
+ Add subprocess to write dirty buffers periodically to reduce
+ checkpoint writes (Jan)
+
+ In previous releases, the checkpoint process, which runs every few
+ minutes, would write all dirty buffers to the operating system's
+ buffer cache then flush all dirty operating system buffers to
+ disk. This resulted in a periodic spike in disk usage that often
+ hurt performance. The new code uses a background writer to trickle
+ disk writes at a steady pace so checkpoints have far fewer dirty
+ pages to write to disk. Also, the new code does not issue a global
+ sync() call, but instead fsync()s just
+ the files written since the last checkpoint. This should improve
+ performance and minimize degradation during checkpoints.
+
+
+
+
+ Add ability to prolong vacuum to reduce performance impact (Jan)
+
+ On busy systems, VACUUM performs many I/O
+ requests which can hurt performance for other users. This
+ release allows you to slow down VACUUM to
+ reduce its impact on other users, though this increases the
+ total duration of VACUUM.
+
+
+
+
+ Improve B-tree index performance for duplicate keys (Dmitry Tkach, Tom)
+
+ This improves the way indexes are scanned when many duplicate
+ values exist in the index.
+
+
+
+
+ Use dynamically-generated table size estimates while planning (Tom)
+
+ Formerly the planner estimated table sizes using the values seen
+ by the last VACUUM or ANALYZE,
+ both as to physical table size (number of pages) and number of rows.
+ Now, the current physical table size is obtained from the kernel,
+ and the number of rows is estimated by multiplying the table size
+ by the row density (rows per page) seen by the last
+ VACUUM or ANALYZE. This should
+ produce more reliable estimates in cases where the table size has
+ changed significantly since the last housekeeping command.
+
+
+
+
+ Improved index usage with OR clauses (Tom)
+
+ This allows the optimizer to use indexes in statements with many OR
+ clauses that would not have been indexed in the past. It can also use
+ multi-column indexes where the first column is specified and the second
+ column is part of an OR clause.
+
+
+
+
+ Improve matching of partial index clauses (Tom)
+
+ The server is now smarter about using partial indexes in queries
+ involving complex
+
+
+
+
+ Improve performance of the GEQO optimizer (Tom)
+
+ The GEQO optimizer is used to plan queries involving many tables (by
+ default, twelve or more). This release speeds up the way queries are
+ analyzed to decrease time spent in optimization.
+
+
+
+
+ Miscellaneous optimizer improvements
+
+ There is not room here to list all the minor improvements made, but
+ numerous special cases work better than in prior releases.
+
+
+
+
+ Improve lookup speed for C functions (Tom)
+
+ This release uses a hash table to lookup information for dynamically
+ loaded C functions. This improves their speed so they perform nearly as
+ quickly as functions that are built into the server executable.
+
+
+
+
+ Add type-specific ANALYZE statistics
+ capability (Mark Cave-Ayland)
+
+ This feature allows more flexibility in generating statistics
+ for non-standard data types.
+
+
+
+
+ ANALYZE now collects statistics for
+ expression indexes (Tom)
+
+ Expression indexes (also called functional indexes) allow users to
+ index not just columns but the results of expressions and function
+ calls. With this release, the optimizer can gather and use statistics
+ about the contents of expression indexes. This will greatly improve
+ the quality of planning for queries in which an expression index is
+ relevant.
+
+
+
+
+ New two-stage sampling method for ANALYZE
+ (Manfred Koizar)
+
+ This gives better statistics when the density of valid rows is very
+ different in different regions of a table.
+
+
+
+
+ Speed up TRUNCATE (Tom)
+
+ This buys back some of the performance loss observed in 7.4, while still
+ keeping TRUNCATE transaction-safe.
+
+
+
+
+
+
+
+
+
Server Changes
+
+
+
+ Add WAL file archiving and point-in-time recovery (Simon Riggs)
+
+
+
+
+ Add tablespaces so admins can control disk layout (Gavin)
+
+
+
+
+ Add a built-in log rotation program (Andreas Pflug)
+
+ It is now possible to log server messages conveniently without
+ relying on either
syslog or an external log+ rotation program.
+
+
+
+
+ Add new read-only server configuration parameters to show server
+ compile-time settings: block_size,
+ integer_datetimes, max_function_args,
+ max_identifier_length, max_index_keys (Joe)
+
+
+
+
+ Make quoting of sameuser, samegroup, and
+ all remove special meaning of these terms in
+ pg_hba.conf (Andrew)
+
+
+
+
+ Use clearer IPv6 name ::1/128 for
+ localhost in default pg_hba.conf (Andrew)
+
+
+
+
+ Use CIDR format in pg_hba.conf examples (Andrew)
+
+
+
+
+ Rename server configuration parameters SortMem and
+ VacuumMem to work_mem and
+ maintenance_work_mem (Old names still supported) (Tom)
+
+ This change was made to clarify that bulk operations such as index and
+ foreign key creation use maintenance_work_mem, while
+ work_mem is for workspaces used during query execution.
+
+
+
+
+ Allow logging of session disconnections using server configuration
+ log_disconnections (Andrew)
+
+
+
+
+ Add new server configuration parameter log_line_prefix to
+ allow control of information emitted in each log line (Andrew)
+
+ Available information includes user name, database name, remote IP
+ address, and session start time.
+
+
+
+
+ Remove server configuration parameters log_pid,
+ log_timestamp, log_source_port; functionality
+ superseded by log_line_prefix (Andrew)
+
+
+
+
+ Replace the virtual_host and tcpip_socket
+ parameters with a unified listen_addresses parameter
+ (Andrew, Tom)
+
+ virtual_host could only specify a single IP address to
+ listen on. listen_addresses allows multiple addresses
+ to be specified.
+
+
+
+
+ Listen on localhost by default, which eliminates the need for the
+
+
+ Listening on localhost (127.0.0.1) opens no new
+ security holes but allows configurations like Windows and JDBC,
+ which do not support local sockets, to work without special
+ adjustments.
+
+
+
+
+ Remove syslog server configuration parameter, and add more
+ logical log_destination variable to control log output
+ location (Magnus)
+
+
+
+
+ Change server configuration parameter log_statement to take
+ values all, mod, ddl, or
+ none to select which queries are logged (Bruce)
+
+ This allows administrators to log only data definition changes or
+ only data modification statements.
+
+
+
+
+ Some logging-related configuration parameters could formerly be adjusted
+ by ordinary users, but only in the more verbose direction.
+ They are now treated more strictly: only superusers can set them.
+ However, a superuser may use ALTER USER to provide per-user
+ settings of these values for non-superusers. Also, it is now possible
+ for superusers to set values of superuser-only configuration parameters
+ via PGOPTIONS.
+
+
+
+
+ Allow configuration files to be placed outside the data directory (mlw)
+
+ By default, configuration files are kept in the cluster's top directory.
+ With this addition, configuration files can be placed outside the
+ data directory, easing administration.
+
+
+
+
+ Plan prepared queries only when first executed so constants can be
+ used for statistics (Oliver Jowett)
+
+ Prepared statements plan queries once and execute them many
+ times. While prepared queries avoid the overhead of re-planning
+ on each use, the quality of the plan suffers from not knowing the exact
+ parameters to be used in the query. In this release, planning of
+ unnamed prepared statements is delayed until the first execution,
+ and the actual parameter values of that execution are used as
+ optimization hints. This allows use of out-of-line parameter passing
+ without incurring a performance penalty.
+
+
+
+
+ Allow DECLARE CURSOR to take parameters
+ (Oliver Jowett)
+
+ It is now useful to issue DECLARE CURSOR in a
+ Parse message with parameters. The parameter values
+ sent at Bind time will be substituted into the
+ execution of the cursor's query.
+
+
+
+
+ Fix hash joins and aggregates of inet and
+ cidr data types (Tom)
+
+ Release 7.4 handled hashing of mixed inet and
+ cidr values incorrectly. (This bug did not exist
+ in prior releases because they wouldn't try to hash either
+ data type.)
+
+
+
+
+ Make log_duration print only when log_statement
+ prints the query (Ed L.)
+
+
+
+
+
+
+
+
+
Query Changes
+
+
+
+ Add savepoints (nested transactions) (Alvaro)
+
+
+
+
+ Unsupported isolation levels are now accepted and promoted to the
+ nearest supported level (Peter)
+
+ The SQL specification states that if a database doesn't support a
+ specific isolation level, it should use the next more restrictive level.
+ This change complies with that recommendation.
+
+
+
+
+ Allow BEGIN WORK to specify transaction
+ isolation levels like START TRANSACTION does
+ (Bruce)
+
+
+
+
+ Fix table permission checking for cases in which rules generate
+ a query type different from the originally submitted query (Tom)
+
+
+
+
+ Implement dollar quoting to simplify single-quote usage (Andrew, Tom,
+ David Fetter)
+
+ In previous releases, because single quotes had to be used to
+ quote a function's body, the use of single quotes inside the
+ function text required use of two single quotes or other error-prone
+ notations. With this release we add the ability to use "dollar
+ quoting" to quote a block of text. The ability to use different
+ quoting delimiters at different nesting levels greatly simplifies
+ the task of quoting correctly, especially in complex functions.
+ Dollar quoting can be used anywhere quoted text is needed.
+
+
+
+
+ Make CASE val WHEN compval1 THEN ... evaluate val only once (Tom)
+
+
+ times. This has benefits when the expression is complex or is
+ volatile.
+
+
+
+
+ Test
+ aggregate query (Tom)
+
+ Fixes improper failure of cases such as SELECT SUM(win)/SUM(lose)
+ ... GROUP BY ... HAVING SUM(lose) > 0. This should work but formerly
+ could fail with divide-by-zero.
+
+
+
+
+ Replace max_expr_depth parameter with
+ max_stack_depth parameter, measured in kilobytes of stack
+ size (Tom)
+
+ This gives us a fairly bulletproof defense against crashing due to
+ runaway recursive functions. Instead of measuring the depth of expression
+ nesting, we now directly measure the size of the execution stack.
+
+
+
+
+ Allow arbitrary row expressions (Tom)
+
+ This release allows SQL expressions to contain arbitrary composite
+ types, that is, row values. It also allows functions to more easily
+ take rows as arguments and return row values.
+
+
+
+
+ Allow
+ in row and subselect comparisons (Fabien Coelho)
+
+
+
+
+ Avoid locale-specific case conversion of basic ASCII letters in
+ identifiers and keywords (Tom)
+
+ This solves the Turkish problem with mangling of words
+ containing I and i. Folding of characters
+ outside the 7-bit-ASCII set is still locale-aware.
+
+
+
+
+ Improve syntax error reporting (Fabien, Tom)
+
+ Syntax error reports are more useful than before.
+
+
+
+
+ Change EXECUTE to return a completion tag
+ matching the executed statement (Kris Jurka)
+
+ Previous releases return an EXECUTE tag for
+ any EXECUTE call. In this release, the tag
+ returned will reflect the command executed.
+
+
+
+
+ Avoid emitting
+
+ Such a clause makes no logical sense, but in some cases the rule
+ decompiler formerly produced this syntax.
+
+
+
+
+
+
+
+
+
Object Manipulation Changes
+
+
+
+ Add COMMENT ON for casts, conversions, languages,
+ operator classes, and large objects (Christopher)
+
+
+
+
+ Add new server configuration parameter default_with_oids to
+ control whether tables are created with OIDs by default (Neil)
+
+ This allows administrators to control whether CREATE
+ TABLE commands create tables with or without OID
+ columns by default. (Note: the current factory default setting for
+ default_with_oids is TRUE, but the default
+ will become FALSE in future releases.)
+
+
+
+
+ Add
+ CREATE TABLE AS (Neil)
+
+
+
+
+ Allow ALTER TABLE DROP COLUMN to drop an OID
+ column (ALTER TABLE SET WITHOUT OIDS still works)
+ (Tom)
+
+
+
+
+ Allow composite types as table columns (Tom)
+
+
+
+
+ Allow ALTER ... ADD COLUMN with defaults and
+
+
+ It is now possible for
+ that is not initially filled with NULLs, but with a specified
+ default value.
+
+
+
+
+ Add ALTER COLUMN TYPE to change column's type (Rod)
+
+ It is now possible to alter a column's data type without dropping
+ and re-adding the column.
+
+
+
+
+ Allow multiple ALTER actions in a single ALTER
+ TABLE command (Rod)
+
+ This is particularly useful for ALTER commands that
+ rewrite the table (which include
+
+ ALTER commands together, the table need be rewritten
+ only once.
+
+
+
+
+ Allow ALTER TABLE to add SERIAL
+ columns (Tom)
+
+ This falls out from the new capability of specifying defaults for new
+ columns.
+
+
+
+
+ Allow changing the owners of aggregates, conversions, databases,
+ functions, operators, operator classes, schemas, types, and tablespaces
+ (Christopher, Euler Taveira de Oliveira)
+
+ Previously this required modifying the system tables directly.
+
+
+
+
+ Allow temporary object creation to be limited to
+ DEFINER functions (Sean Chittenden)
+
+
+
+
+ Add
+
+ Prior to this release, there was no way to clear an auto-cluster
+ specification except to modify the system tables.
+
+
+
+
+ Constraint/Index/SERIAL names are now
+ table_column_type
+ with numbers appended to guarantee uniqueness within the schema
+ (Tom)
+
+ The SQL specification states that such names should be unique
+ within a schema.
+
+
+
+
+ Add pg_get_serial_sequence() to return a
+ SERIAL column's sequence name (Christopher)
+
+ This allows automated scripts to reliably find the SERIAL
+ sequence name.
+
+
+
+
+ Warn when primary/foreign key data type mismatch requires costly lookup
+
+
+
+
+ New ALTER INDEX command to allow moving of indexes
+ between tablespaces (Gavin)
+
+
+
+
+ Make ALTER TABLE OWNER change dependent sequence
+ ownership too (Alvaro)
+
+
+
+
+
+
+
+
+
+
Utility Command Changes
+
+
+
+ Allow CREATE SCHEMA to create triggers,
+ indexes, and sequences (Neil)
+
+
+
+
+ Add
+ Coelho)
+
+ This allows
+
+
+
+
+
+ Add
+
+ This allows the LOCK command to fail if it
+ would have to wait for the requested lock.
+
+
+
+
+ Allow COPY to read and write
+ comma-separated-value (CSV) files (Andrew, Bruce)
+
+
+
+
+ Generate error if the COPY delimiter and NULL
+ string conflict (Bruce)
+
+
+
+
+ GRANT/REVOKE behavior
+ follows the SQL spec more closely
+
+
+
+
+ Avoid locking conflict between CREATE INDEX
+ and CHECKPOINT (Tom)
+
+ In 7.3 and 7.4, a long-running B-tree index build could block concurrent
+ CHECKPOINTs from completing, thereby causing WAL bloat because the
+ WAL log could not be recycled.
+
+
+
+
+ Database-wide ANALYZE does not hold locks
+ across tables (Tom)
+
+ This reduces the potential for deadlocks against other backends
+ that want exclusive locks on tables. To get the benefit of this
+ change, do not execute database-wide ANALYZE
+ inside a transaction block (BEGIN block); it
+ must be able to commit and start a new transaction for each
+ table.
+
+
+
+
+ REINDEX does not exclusively lock the index's
+ parent table anymore
+
+ The index itself is still exclusively locked, but readers of the
+ table can continue if they are not using the particular index
+ being rebuilt.
+
+
+
+
+ Erase MD5 user passwords when a user is renamed (Bruce)
+
+
PostgreSQL uses the user name as salt
+ when encrypting passwords via MD5. When a user's name is changed,
+ the salt will no longer match the stored MD5 password, so the
+ stored password becomes useless. In this release a notice is
+ generated and the password is cleared. A new password must then
+ be assigned if the user is to be able to log in with a password.
+
+
+
+
+ New
pg_ctl +
+ Windows does not have a kill command to send signals to
+ backends so this capability was added to
pg_ctl.+
+
+
+
+ Information schema improvements
+
+
+
+
+ Add
+
initdb so the initial password can be
+ set by GUI tools (Magnus)
+
+
+
+
+ Detect locale/encoding mismatch in
+
+
+
+
+ Add
+ register Windows operating system service (Dave Page)
+
+
+
+
+
+
+
+
+
Data Type and Function Changes
+
+
+
+ More complete support for composite types (row types) (Tom)
+
+ Composite values can be used in many places where only scalar values
+ worked before.
+
+
+
+
+ Reject non-rectangular array values as erroneous (Joe)
+
+ Formerly, array_in would silently build a
+ surprising result.
+
+
+
+
+ Overflow in integer arithmetic operations is now detected (Tom)
+
+
+
+
+ The arithmetic operators associated with the single-byte
+ "char" data type have been removed.
+
+ Formerly, the parser would select these operators in many situations
+ where an unable to select an operator error would be more
+ appropriate, such as null * null. If you actually want
+ to do arithmetic on a "char" column, you can cast it to
+ integer explicitly.
+
+
+
+
+ Syntax checking of array input values considerably tightened up (Joe)
+
+ Junk that was previously allowed in odd places with odd results
+ now causes an ERROR, for example, non-whitespace
+ after the closing right brace.
+
+
+
+
+ Empty-string array element values must now be written as
+ "", rather than writing nothing (Joe)
+
+ Formerly, both ways of writing an empty-string element value were
+ allowed, but now a quoted empty string is required. The case where
+ nothing at all appears will probably be considered to be a NULL
+ element value in some future release.
+
+
+
+
+ Array element trailing whitespace is now ignored (Joe)
+
+ Formerly leading whitespace was ignored, but trailing whitespace
+ between an element value and the delimiter or right brace was
+ significant. Now trailing whitespace is also ignored.
+
+
+
+
+ Emit array values with explicit array bounds when lower bound is not one
+ (Joe)
+
+
+
+
+ Accept YYYY-monthname-DD as a date string (Tom)
+
+
+
+
+ Make netmask and hostmask functions
+ return maximum-length mask length (Tom)
+
+
+
+
+ Change factorial function to return numeric (Gavin)
+
+ Returning numeric allows the factorial function to
+ work for a wider range of input values.
+
+
+
+
+ to_char/to_date() date conversion
+ improvements (Kurt Roeckx, Fabien Coelho)
+
+
+
+
+ Make length() disregard trailing spaces in
+ CHAR(n) (Gavin)
+
+ This change was made to improve consistency: trailing spaces are
+ semantically insignificant in CHAR(n) data, so they
+ should not be counted by length().
+
+
+
+
+ Warn about empty string being passed to
+ OID/float4/float8 data types (Neil)
+
+ 8.1 will throw an error instead.
+
+
+
+
+ Allow leading or trailing whitespace in
+ int2/int4/int8/float4/float8
+ input routines
+ (Neil)
+
+
+
+
+ Better support for IEEE Infinity and NaN
+ values in float4/float8 (Neil)
+
+ These should now work on all platforms that support IEEE-compliant
+ floating point arithmetic.
+
+
+
+
+ Add
+
+
+
+
+ Fix to_char for 1 BC
+ (previously it returned 1 AD) (Bruce)
+
+
+
+
+ Fix date_part(year) for BC dates (previously it
+ returned one less than the correct year) (Bruce)
+
+
+
+
+ Fix date_part() to return the proper millennium and
+ century (Fabien Coelho)
+
+ In previous versions, the century and millennium results had a wrong
+ number and started in the wrong year, as compared to standard
+ reckoning of such things.
+
+
+
+
+ Add ceiling() as an alias for ceil(),
+ and power() as an alias for pow() for
+ standards compliance (Neil)
+
+
+
+
+ Change ln(), log(),
+ power(), and sqrt() to emit the correct
+ SQLSTATE error codes for certain error conditions, as
+ specified by SQL:2003 (Neil)
+
+
+
+
+ Add width_bucket() function as defined by SQL:2003 (Neil)
+
+
+
+
+ Add generate_series() functions to simplify working
+ with numeric sets (Joe)
+
+
+
+
+ Fix upper/lower/initcap() functions to work with
+ multibyte encodings (Tom)
+
+
+
+
+ Add boolean and bitwise integer
+ aggregates (Fabien Coelho)
+
+
+
+
+ New session information functions to return network addresses for client
+ and server (Sean Chittenden)
+
+
+
+
+ Add function to determine the area of a closed path (Sean Chittenden)
+
+
+
+
+ Add function to send cancel request to other backends (Magnus)
+
+
+
+
+ Add interval plus datetime operators (Tom)
+
+ The reverse ordering, datetime plus interval,
+ was already supported, but both are required by the SQL standard.
+
+
+
+
+ Casting an integer to BIT(N) selects the rightmost N bits
+ of the integer
+ (Tom)
+
+ In prior releases, the leftmost N bits were selected, but this was
+ deemed unhelpful, not to mention inconsistent with casting from bit
+ to int.
+
+
+
+
+ Require CIDR values to have all non-masked bits be zero
+ (Kevin Brintnall)
+
+
+
+
+
+
+
+
+
Server-Side Language Changes
+
+
+
+ In READ COMMITTED serialization mode, volatile functions
+ now see the results of concurrent transactions committed up to the
+ beginning of each statement within the function, rather than up to the
+ beginning of the interactive command that called the function.
+
+
+
+
+ Functions declared STABLE or IMMUTABLE always
+ use the snapshot of the calling query, and therefore do not see the
+ effects of actions taken after the calling query starts, whether in
+ their own transaction or other transactions. Such a function must be
+ read-only, too, meaning that it cannot use any SQL commands other than
+ SELECT. There is a considerable performance gain from
+ declaring a function STABLE or IMMUTABLE
+ rather than VOLATILE.
+
+
+
+
+ Non-deferred
+ after completion of the triggering query, rather than upon
+ finishing the current interactive command. This makes a difference
+ when the triggering query occurred within a function: the trigger
+ is invoked before the function proceeds to its next operation. For
+ example, if a function inserts a new row into a table, any
+ non-deferred foreign key checks occur before proceeding with the
+ function.
+
+
+
+
+ Allow function parameters to be declared with names (Dennis Bjorklund)
+
+ This allows better documentation of functions. Whether the names
+ actually do anything depends on the specific function language
+ being used.
+
+
+
+
+ Allow PL/pgSQL parameter names to be referenced in the function (Dennis Bjorklund)
+
+ This basically creates an automatic alias for each named parameter.
+
+
+
+
+ Do minimal syntax checking of PL/pgSQL functions at creation time (Tom)
+
+ This allows us to catch simple syntax errors sooner.
+
+
+
+
+ More support for composite types (row and record variables) in PL/pgSQL
+
+ For example, it now works to pass a rowtype variable to another function
+ as a single variable.
+
+
+
+
+ Default values for PL/pgSQL variables can now reference previously
+ declared variables
+
+
+
+
+ Improve parsing of PL/pgSQL FOR loops (Tom)
+
+ Parsing is now driven by presence of ".." rather than
+ data type of
+ correct functions, but should result in more understandable error
+ messages when a mistake is made.
+
+
+
+
+ Major overhaul of PL/Perl server-side language (Command Prompt, Andrew Dunstan)
+
+
+
+
+ In PL/Tcl, SPI commands are now run in subtransactions. If an error
+ occurs, the subtransaction is cleaned up and the error is reported
+ as an ordinary Tcl error, which can be trapped with catch.
+ Formerly, it was not possible to catch such errors.
+
+
+
+
+ Accept ELSEIF in PL/pgSQL (Neil)
+
+ Previously PL/pgSQL only allowed ELSIF, but many people
+ are accustomed to spelling this keyword ELSEIF.
+
+
+
+
+
+
+
+
+
<application>psql</> Changes
+
+
+
+ Improve
psql information display about database+ objects (Christopher)
+
+
+
+
+ Allow
psql to display group membership in+ \du and \dg (Markus Bertheau)
+
+
+
+
+ Prevent
psql \dn from showing+ temporary schemas (Bruce)
+
+
+
+
+ Allow
psql to handle tilde user expansion for file+ names (Zach Irmen)
+
+
+
+
+ Allow
psql to display fancy prompts, including+ color, via
readline (Reece Hart, Chet Ramey)+
+
+
+
+ Make
psql \copy match COPY command syntax+ fully (Tom)
+
+
+
+
+ Show the location of syntax errors (Fabien Coelho, Tom)
+
+
+
+
+ Add
CLUSTER information to
psql+ \d display
+ (Bruce)
+
+
+
+
+ Change
psql \copy stdin/stdout to read+ from command input/output (Bruce)
+
+
+
+
+ Add
+
psql's stdin/stdout (Mark+ Feit)
+
+
+
+
+ Add global
psql configuration file, psqlrc.sample+ (Bruce)
+
+ This allows a central file where global
psql startup commands can+ be stored.
+
+
+
+
+ Have
psql \d+ indicate if the table+ has an OID column (Neil)
+
+
+
+
+ On Windows, use binary mode in
psql when reading files so control-Z+ is not seen as end-of-file
+
+
+
+
+ Have \dn+ show permissions and description for schemas (Dennis
+ Bjorklund)
+
+
+
+
+ Improve tab completion support (Stefan Kaltenbrunn, Greg Sabino Mullane)
+
+
+
+
+ Allow boolean settings to be set using upper or lower case (Michael Paesold)
+
+
+
+
+
+
+
+
+
<application>pg_dump</> Changes
+
+
+
+ Use dependency information to improve the reliability of
+
+ This should solve the longstanding problems with related objects
+ sometimes being dumped in the wrong order.
+
+
+
+
+ Have
pg_dump output objects in alphabetical order if possible (Tom)+
+ This should make it easier to identify changes between
+ dump files.
+
+
+
+
+ Allow
pg_restore to ignore some SQL errors (Fabien Coelho)+
+ This makes
pg_restore's behavior similar to the+ results of feeding a
pg_dump output script to+
psql. In most cases, ignoring errors and plowing+ ahead is the most useful thing to do. Also added was a pg_restore
+ option to give the old behavior of exiting on an error.
+
+
+
+
+
pg_restore + objects' schema names
+
+
+
+
+ New begin/end markers in
pg_dump text output (Bruce)+
+
+
+
+ Add start/stop times for
+
pg_dump/pg_dumpall in verbose mode+ (Bruce)
+
+
+
+
+ Allow most
pg_dump options in+
pg_dumpall (Christopher)+
+
+
+
+ Have
pg_dump use ALTER OWNER rather+ than SET SESSION AUTHORIZATION by default
+ (Christopher)
+
+
+
+
+
+
+
+
+
libpq Changes
+
+
+
+ Make libpq's
+
+
+
+
+ Add PQmbdsplen() which returns the display length
+ of a character (Tatsuo)
+
+
+
+
+ Add thread locking to
SSL and+
Kerberos connections (Manfred Spraul)+
+
+
+
+ Allow PQoidValue(), PQcmdTuples(), and
+ PQoidStatus() to work on EXECUTE
+ commands (Neil)
+
+
+
+
+ Add PQserverVersion() to provide more convenient
+ access to the server version number (Greg Sabino Mullane)
+
+
+
+
+ Add PQprepare/PQsendPrepared() functions to support
+ preparing statements without necessarily specifying the data types
+ of their parameters (Abhijit Menon-Sen)
+
+
+
+
+ Many ECPG improvements, including SET DESCRIPTOR (Michael)
+
+
+
+
+
+
+
+
+
Source Code Changes
+
+
+
+ Allow the database server to run natively on Windows (Claudio, Magnus, Andrew)
+
+
+
+
+ Shell script commands converted to C versions for Windows support (Andrew)
+
+
+
+
+ Create an extension makefile framework (Fabien Coelho, Peter)
+
+ This simplifies the task of building extensions outside the original
+ source tree.
+
+
+
+
+ Support relocatable installations (Bruce)
+
+ Directory paths for installed files (such as the
+ /share directory) are now computed relative to the
+ actual location of the executables, so that an installation tree
+ can be moved to another place without reconfiguring and
+ rebuilding.
+
+
+
+
+ Use
+ allow
+
+
+
+
+ Add
+
+
+
+
+ Upgrade to
DocBook V4.2 SGML (Peter)+
+
+
+
+ New
PostgreSQL CVS tag (Marc)+
+ This was done to make it easier for organizations to manage their
+ own copies of the
PostgreSQL+
CVS repository. File version stamps from the master+ repository will not get munged by checking into or out of a copied
+ repository.
+
+
+
+
+ Clarify locking code (Manfred Koizar)
+
+
+
+
+ Buffer manager cleanup (Neil)
+
+
+
+
+ Decouple platform tests from CPU spinlock code (Bruce, Tom)
+
+
+
+
+ Add inlined test-and-set code on PA-RISC for
gcc+ (ViSolve, Tom)
+
+
+
+
+ Improve i386 spinlock code (Manfred Spraul)
+
+
+
+
+ Clean up spinlock assembly code to avoid warnings from newer
+
+
+
+
+ Remove JDBC from source tree; now a separate project
+
+
+
+
+ Remove the libpgtcl client interface; now a separate project
+
+
+
+
+ More accurately estimate memory and file descriptor usage (Tom)
+
+
+
+
+ Improvements to the Mac OS X startup scripts (Ray A.)
+
+
+
+
+ New fsync() test program (Bruce)
+
+
+
+
+ Major documentation improvements (Neil, Peter)
+
+
+
+
+ Remove
pg_encoding; not needed
+ anymore
+
+
+
+
+ Remove
pg_id; not needed anymore
+
+
+
+
+ Remove
initlocation; not needed
+ anymore
+
+
+
+
+ Auto-detect thread flags (no more manual testing) (Bruce)
+
+
+
+
+ Use Olson's public domain
timezone library (Magnus)+
+
+
+
+ With threading enabled, use thread flags on Unixware for
+ backend executables too (Bruce)
+
+ Unixware cannot mix threaded and non-threaded object files in the
+ same executable, so everything must be compiled as threaded.
+
+
+
+
+
psql now uses a flex-generated+ lexical analyzer to process command strings
+
+
+
+
+ Reimplement the linked list data structure used throughout the
+ backend (Neil)
+
+ This improves performance by allowing list append and length
+ operations to be more efficient.
+
+
+
+
+ Allow dynamically loaded modules to create their own server configuration
+ parameters (Thomas Hallgren)
+
+
+
+
+ New Brazilian version of FAQ (Euler Taveira de Oliveira)
+
+
+
+
+ Add French FAQ (Guillaume Lelarge)
+
+
+
+
+ New
pgevent for Windows logging+
+
+
+
+ Make libpq and ECPG build as proper shared libraries on OS X (Tom)
+
+
+
+
+
+
+
+
+
Contrib Changes
+
+
+
+ Overhaul of contrib/dblink (Joe)
+
+
+
+
+ contrib/dbmirror improvements (Steven Singer)
+
+
+
+
+ New contrib/xml2 (John Gray, Torchbox)
+
+
+
+
+ Updated contrib/mysql
+
+
+
+
+ New version of contrib/btree_gist (Teodor)
+
+
+
+
+ New contrib/trgm, trigram matching for
+
+
+
+
+ Many contrib/tsearch2 improvements (Teodor)
+
+
+
+
+ Add double metaphone to contrib/fuzzystrmatch (Andrew)
+
+
+
+
+ Allow contrib/pg_autovacuum to run as a Windows service (Dave Page)
+
+
+
+
+ Add functions to contrib/dbsize (Andreas Pflug)
+
+
+
+
+ Removed contrib/pg_logger: obsoleted by integrated logging
+ subprocess
+
+
+
+
+ Removed contrib/rserv: obsoleted by various separate projects
+
+
+
+
+
+
+
+
+
Release 7.4.8
ALTER TABLE SET WITHOUT OIDS
-
-
+
+
Release 7.4.7
GMT
-
-
+
+
Release 7.4.6
ECPG prepare statement
-
-
+
+
Release 7.4.5
-
-
+
+
Release 7.4.4
Translation updates (various contributors)
-
-
+
+
Release 7.4.3
Numerous translation updates (various contributors)
-
-
+
+
Release 7.4.2
-
-
+
+
Release 7.4.1
sgml-local-ecat-files:nil
End:
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projects / postgresql.git / commitdiff