1 TODO list for PostgreSQL
2 ========================
3 Last updated: Mon Aug 26 18:01:45 EDT 2002
5 Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
7 The most recent version of this document can be viewed at
8 the PostgreSQL web site, http://www.PostgreSQL.org.
10 A dash (-) marks changes that will appear in the upcoming 7.3 release.
12 Bracketed items "[]" have more detailed.
18 * Add replication of distributed databases [replication]
21 o master/slave replication
22 o multi-master replication
23 o partition data across servers
24 o sample implementation in contrib/rserv
25 o queries across databases or servers (two-phase commit)
26 o allow replication over unreliable or non-persistent links
27 o http://gborg.postgresql.org/project/pgreplication/projdisplay.php
28 * Point-in-time data recovery using backup and write-ahead log
34 * Allow elog() to return error codes, module name, file name, line
35 number, not just messages (Peter E)
36 * Add error codes (Peter E)
37 * Make error messages more consistent [error]
38 * -Change DEBUG startup tag to LOG (Bruce)
39 * Show location of syntax error in query [yacc]
40 * -Add getpid() function to backend
41 * Allow logging of query durations
47 * -Improve control over user privileges, including table creation
48 * -Allow user/group names to be specified directly in pg_hba.conf (Bruce)
49 * -Add PGPASSWORDFILE environment variable or ~/.pgpass to store
50 user/host/password combinations
51 * Remove PGPASSWORD because it is insecure on some OS's, in 7.4
52 * Make single-user local access permissions the default by limiting
53 permissions on the socket file (Peter E)
54 * -Allow permissions for functions (Peter E)
55 * -Allow object creation to be disabled for specific users
62 * -Make it easier to create a database owned by someone who can't createdb,
63 perhaps CREATE DATABASE dbname WITH OWNER = "user" (Gavin)
64 * -Make equals sign optional in CREATE DATABASE WITH param = 'val'
65 * Remove unreferenced table files and temp tables during database vacuum
66 or postmaster startup (Bruce)
67 * Remove behavior of postmaster -o after making postmaster/postgres
69 * -Prevent SIGHUP and 'pg_ctl reload' from changing command line
70 specified parameters to postgresql.conf defaults (Peter E)
71 * Allow easy display of usernames in a group
72 * Allow configuration files to be specified in a different directory
73 * Reserve last few process slots for super-user if max_connections reached
74 * Add GUC parameter to print queries that generate errors
79 * -Add domain capability (Rod Taylor)
80 * Add IPv6 capability to INET/CIDR types
81 * Remove Money type, add money formatting for decimal type
82 * -SELECT cash_out(2) crashes because of opaque
83 * Declare typein/out functions in pg_proc with a special "C string" data type
84 * Functions returning sets do not totally work
85 * Change factorial to return a numeric
86 * Change NUMERIC data type to use base 10,000 internally
87 * Change NUMERIC to enforce the maximum precision, and increase it
88 * Add function to return compressed length of TOAST data values (Tom)
89 * -Add GUC parameter for DATESTYLE
90 * Allow INET subnet tests using non-constants
91 * Allow bytea to handle LIKE with non-TEXT patterns
95 o Store binary-compatible type information in the system
96 o Allow better handling of numeric constants, type conversion
98 o SELECT col FROM tab WHERE numeric_col = 10.1 fails, requires quotes
101 o Allow nulls in arrays
102 o Allow arrays to be ORDER'ed
103 o Ensure we have array-eq operators for every built-in array type
104 o Support construction of array result values in expressions
107 o Improve vacuum of large objects, like /contrib/vacuumlo
108 o Add security checking for large objects
109 o Make file in/out interface for TOAST columns, similar to large object
110 interface (force out-of-line storage and no compression)
111 o Auto-delete large objects when referencing row is deleted
114 Multi-Language Support
115 ======================
117 * Add NCHAR (as distinguished from ordinary varchar),
118 * Allow LOCALE on a per-column basis, default to ASCII
119 * Support multiple simultaneous character sets, per SQL92
120 * Allow setting database character set without multibyte enabled
121 * Improve Unicode combined character handling
122 * Optimize locale to have minimal performance impact when not used (Peter E)
123 * Add octet_length_server() and octet_length_client() (Thomas, Tatsuo)
124 * Make octet_length_client the same as octet_length() (?)
125 * Prevent mismatch of frontend/backend encodings from converting bytea
126 data from being interpreted as encoded strings
131 * Automatically create rules on views so they are updateable, per SQL92 [view]
132 * Add the functionality for WITH CHECK OPTION clause of CREATE VIEW
133 * Allow NOTIFY in rules involving conditionals
134 * Have views on temporary tables exist in the temporary namespace
135 * Move psql backslash information into views
136 * Allow RULE recompilation
137 * -Remove brackets as multi-statement rule grouping, must use parens (Bruce)
138 * Prevent aggregates from being used in rule WHERE clauses
144 * Allow CREATE INDEX zman_index ON test (date_trunc( 'day', zman ) datetime_ops)
145 fails index can't store constant parameters
146 * Order duplicate index entries by tid for faster heap lookups
147 * Allow inherited tables to inherit index, UNIQUE constraint, and primary
148 key, foreign key [inheritance]
149 * UNIQUE INDEX on base column not honored on inserts from inherited table
150 INSERT INTO inherit_table (unique_index_col) VALUES (dup) should fail
152 * -Allow UPDATE/DELETE on inherited table
153 * Have UPDATE/DELETE clean out indexes
154 * Add UNIQUE capability to non-btree indexes
155 * Add btree index support for reltime, tinterval, regproc
156 * Add rtree index support for line, lseg, path, point
157 * Certain indexes will not shrink, e.g. indexes on ever-increasing
158 columns and indexes with many duplicate keys
159 * Use indexes for min() and max() or convert to SELECT col FROM tab ORDER
160 BY col DESC LIMIT 1 if appropriate index exists and WHERE clause acceptible
161 * Allow LIKE indexing optimization for non-ASCII locales
162 * Use index to restrict rows returned by multi-key index when used with
163 non-consecutive keys or OR clauses, so fewer heap accesses
164 * Be smarter about insertion of already-ordered data into btree index
165 * -Add deleted bit to index tuples to reduce heap access
166 * Prevent index uniqueness checks when UPDATE does not modifying column
167 * Use bitmaps to fetch heap pages in sequential order [performance]
168 * Use bitmaps to combine existing indexes [performance]
169 * Improve handling of index scans for NULL
170 * Allow SELECT * FROM tab WHERE int2col = 4 to use int2col index, int8,
171 float4, numeric/decimal too [optimizer]
172 * Add FILLFACTOR to btree index creation
173 * Improve concurrency in GIST
174 * Improve concurrency of hash indexes (Neil Conway)
175 * -Test hash index performance and discourage usage
181 * -Add SIMILAR TO to allow character classes, 'pg_[a-c]%'
182 * Add BETWEEN ASYMMETRIC/SYMMETRIC (Christopher)
183 * -Remove LIMIT #,# and force use LIMIT and OFFSET clauses in 7.3 (Bruce)
184 * Allow LIMIT/OFFSET to use expressions
185 * -Disallow TRUNCATE on tables that are involved in referential constraints
186 * Add OR REPLACE clauses to non-FUNCTION object creation
187 * CREATE TABLE AS can not determine column lengths from expressions [atttypmod]
188 * Allow UPDATE to handle complex aggregates [update]
189 * -Prevent create/drop scripts from allowing extra args (Bruce)
190 * Allow command blocks to ignore certain types of errors
191 * Allow backslash handling in quoted strings to be disabled for portability
192 * Return proper effected tuple count from complex commands [return]
193 * Allow DELETE to handle table aliases for self-joins [delete]
196 o ALTER TABLE ADD COLUMN does not honor DEFAULT and non-CHECK CONSTRAINT
197 o ALTER TABLE ADD COLUMN to inherited table put column in wrong place
199 o -Add ALTER TABLE DROP COLUMN feature
201 o -Add ALTER TABLE DROP non-CHECK CONSTRAINT
202 o -ALTER TABLE ADD PRIMARY KEY (Tom)
203 o -ALTER TABLE ADD UNIQUE (Tom)
204 o -ALTER TABLE ALTER COLUMN SET/DROP NOT NULL (Christopher Kings-Lynne)
205 o ALTER TABLE ADD COLUMN column SERIAL doesn't create sequence
206 o ALTER TABLE ADD COLUMN column DEFAULT should fill existing
207 rows with DEFAULT value
208 o -Have ALTER TABLE OWNER change all dependant objects like indexes
209 o Add ALTER TABLE tab SET WITHOUT OIDS
212 o Cluster all tables at once using pg_index.indisclustered set during
214 o -Prevent loss of indexes, permissions, inheritance
215 o Automatically maintain clustering on a table
218 o -Allow specification of column names
219 o Allow dump/load of CSV format
220 o -Change syntax to WITH DELIMITER, (keep old syntax around?)
221 o Allow COPY to report error lines and continue; optionally
222 allow error codes to be specified; requires savepoints or can
223 not be run in a multi-statement transaction
224 o -Generate failure on short COPY lines rather than pad NULLs
227 o Allow BINARY option to SELECT, just like DECLARE
228 o MOVE 0 should not move to end of cursor
229 o Allow UPDATE/DELETE WHERE CURRENT OF cursor using per-cursor tid
230 stored in the backend
231 o Prevent DROP of table being referenced by our own open cursor
232 o Allow cursors outside transactions [cursor]
235 o Allow INSERT/UPDATE of system-generated oid value for a row
236 o Allow INSERT INTO tab (col1, ..) VALUES (val1, ..), (val2, ..)
237 o -Allow INSERT INTO my_table VALUES (a, b, c, DEFAULT, x, y, z, ...)
238 o -Disallow missing columns in INSERT ... VALUES, per ANSI
239 o Allow INSERT/UPDATE ... RETURNING new.col or old.col; handle
243 o -Add command to display locks
244 o -Add SET or BEGIN timeout parameter to cancel query
245 o Add SET REAL_FORMAT and SET DOUBLE_PRECISION_FORMAT using printf args
246 o -Remove SET KSQO option now that OR processing is improved (Tom)
247 o Add SET PERFORMANCE_TIPS option to suggest INDEX, VACUUM, VACUUM
249 o Add SHOW command to see locale
250 o -Allow SHOW to output as a query result, like EXPLAIN
251 o -Abort all SET changes made in an aborted transaction
253 * SERVER-SIDE LANGUAGES
254 o Allow PL/PgSQL's RAISE function to take expressions
255 o -Fix PL/PgSQL to handle quoted mixed-case identifiers
256 o Change PL/PgSQL to use palloc() instead of malloc()
257 o Add untrusted version of plpython
258 o Add plsh server-side shell language (Peter E)
259 o Allow Java server-side programming, http://pljava.sourceforge.net
261 o Fix problems with complex temporary table creation/destruction
262 without using PL/PgSQL EXECUTE, needs cache prevention/invalidation
263 o Fix PL/pgSQL RENAME to work on variables other than OLD/NEW
264 o Improve PL/PgSQL exception handling
265 o Allow parameters to be specified by name and type during
267 o Allow function parameters to be passed by name,
268 get_employee_salary(emp_id => 12345, tax_year => 2001)
269 o Add PL/PgSQL packages
270 o Allow array declarations and other data types in PL/PgSQl DECLARE
271 o Add PL/PgSQL PROCEDURES that can return multiple values
277 * Have pg_dump use LEFT OUTER JOIN in multi-table SELECTs
278 or multiple SELECTS to avoid bad system catalog entries
279 * -Have pg_dump -C dump database location and encoding information
280 * -Allow psql \d to show foreign keys
281 * -Allow psql \d to show temporary table structure (Tom)
282 * Allow psql to show transaction status if backend protocol changes made
283 * Add XML interface: psql, pg_dump, COPY, separate server (?)
284 * Add config file check for $ODBCINI, $HOME/.odbc.ini, installpath/etc/odbc.ini
285 * -Have pg_dump use ADD PRIMARY KEY after COPY, for performance (Neil Conway)
288 o Comprehensive test suite. This may be available already.
289 o -Updateable resultSet
290 o JDBC-standard BLOB support
291 o Error Codes (pending backend implementation)
292 o Support both 'make' and 'ant'
293 o Fix LargeObject API to handle OIDs as unsigned ints
294 o -Implement cancel() method on Statement
295 o Use cursors implicitly to avoid large results (see setCursorName())
296 o -Add support for CallableStatements
297 o Add LISTEN/NOTIFY support to the JDBC driver (Barry)
298 o -Compile under jdk 1.4
301 o Implement set descriptor, using descriptor
302 o Make casts work in variable initializations
304 o Allow multi-threaded use of SQLCA
305 o Solve cardinality > 1 for input descriptors / variables
306 o Understand structure definitions outside a declare section
307 o sqlwarn[6] should be 'W' if the PRECISION or SCALE value specified
308 o Improve error handling
309 o Allow :var[:index] or :var[<integer>] as cvariable for an array var
310 o Add a semantic check level, e.g. check if a table really exists
311 o Fix nested C comments
313 o fix handling of DB attributes that are arrays
317 o Unicode(UCS-2) support
318 o Updatable cursors support
321 Referential Integrity
322 =====================
324 * Add MATCH PARTIAL referential integrity [foreign]
325 * Add deferred trigger queue file (Jan)
326 * -Allow oid to act as a foreign key
327 * Implement dirty reads and use them in RI triggers
328 * Make triggers refer to columns by number, not name
329 * Enforce referential integrity for system tables
330 * -Allow user to control trigger firing order (Tom)
331 * -Add ALTER TRIGGER ... RENAME
332 * Change foreign key constraint for array -> element to mean element
334 * Fix foreign key constraints to not error on intermediate db states (Stephan)
335 * Allow DEFERRABLE UNIQUE constraints
336 * Allow triggers to be disabled [trigger]
342 * -Add pg_depend table for dependency recording; use sysrelid, oid,
343 depend_sysrelid, depend_oid, name
344 * -Auto-destroy sequence on DROP of table with SERIAL; perhaps a separate
346 * Have SERIAL generate non-colliding sequence names when we have
348 * -Prevent column dropping if column is used by foreign key
349 * Propagate column or table renaming to foreign key constraints
350 * -Automatically drop constraints/functions when object is dropped
351 * -Make foreign key constraints clearer in dump file
352 * -Make other constraints clearer in dump file
353 * -Make foreign keys easier to identify
354 * Flush cached query plans when their underlying catalog data changes
355 * Use dependency information to dump data in proper order
361 * Allow autocommit so always in a transaction block
362 * Overhaul bufmgr/lockmgr/transaction manager
363 * Allow savepoints / nested transactions [transactions]
369 * Add sql3 recursive unions
370 * Add the concept of dataspaces/tablespaces [tablespaces]
371 * -Add SQL92 schemas (Tom)
372 * Allow queries across multiple databases [crossdb]
373 * Add pre-parsing phase that converts non-ANSI features to supported features
374 * Allow plug-in modules to emulate features from other databases
375 * SQL*Net listener that makes PostgreSQL appear as an Oracle database
386 * Delay fsync() when other backends are about to commit too [fsync]
387 o Determine optimal commit_delay value
388 * Determine optimal fdatasync/fsync, O_SYNC/O_DSYNC options
389 o Allow multiple blocks to be written to WAL with one write()
394 * Cache most recent query plan(s) (Neil) [prepare]
395 * Shared catalog cache, reduce lseek()'s by caching table size in shared area
396 * Add free-behind capability for large sequential scans (Bruce)
397 * Allow binding query args over FE/BE protocol
398 * Consider use of open/fcntl(O_DIRECT) to minimize OS caching
399 * Make blind writes go through the file descriptor cache
405 * Improve speed with indexes (perhaps recreate index instead) [vacuum]
406 * Reduce lock time by moving tuples with read lock, then write
407 lock and truncate table [vacuum]
408 * Provide automatic running of vacuum in the background (Tom)
414 * Make locking of shared data structures more fine-grained
415 * Add code to detect an SMP machine and handle spinlocks accordingly
416 from distributted.net, http://www1.distributed.net/source,
417 in client/common/cpucheck.cpp
418 * Research use of sched_yield() for spinlock acquisition failure
424 * Experiment with multi-threaded backend [thread]
425 * Add connection pooling [pool]
426 * Allow persistent backends [persistent]
427 * Create a transaction processor to aid in persistent connections and
429 * Do listen() in postmaster and accept() in pre-forked backend
430 * Have pre-forked backend pre-connect to last requested database or pass
431 file descriptor to backend pre-forked for matching database
432 * -Cache system catalog information in per-database files (Tom)
438 * Have after-change WAL write()'s write only modified data to kernel
439 * Reduce number of after-change WAL writes; they exist only to gaurd against
441 * Turn off after-change writes if fsync is disabled (?)
442 * Add WAL index reliability improvement to non-btree indexes
443 * -Reorder postgresql.conf WAL items in order of importance (Bruce)
444 * Remove wal_files postgresql.conf option because WAL files are now recycled
445 * Find proper defaults for postgresql.conf WAL entries
446 * Add checkpoint_min_warning postgresql.conf option to warn about checkpoints
447 that are too frequent
448 * Allow xlog directory location to be specified during initdb, perhaps
455 * Improve Subplan list handling
456 * Allow Subplans to use efficient joins(hash, merge) with upper variable
457 * Improve dynamic memory allocation by introducing tuple-context memory
459 * Add hash for evaluating GROUP BY aggregates
460 * Nested FULL OUTER JOINs don't work (Tom)
461 * Allow merge and hash joins on expressions not just simple variables (Tom)
462 * -Add new pg_proc cachable settings to specify whether function can be
463 evaluated only once or once per query
464 * -Change FIXED_CHAR_SEL to 0.20 from 0.04 to give better selectivity (Bruce)
465 * Make IN/NOT IN have similar performance to EXISTS/NOT EXISTS [exists]
466 * Missing optimizer selectivities for date, r-tree, etc. [optimizer]
467 * Allow ORDER BY ... LIMIT to select top values without sort or index
468 using a sequential scan for highest/lowest values (Oleg)
469 * Inline simple SQL functions to avoid overhead (Tom)
470 * Precompile SQL functions to avoid overhead (Neil Conway)
471 * Add utility to compute accurate random_page_cost value
472 * Improve ability to display optimizer analysis using OPTIMIZER_DEBUG
473 * Use CHECK constraints to improve optimizer decisions
479 * Do async I/O for faster random read-ahead of data
480 * Get faster regex() code from Henry Spencer <henry@zoo.utoronto.ca>
482 * Use mmap() rather than SYSV shared memory or to write WAL files (?) [mmap]
483 * Improve caching of attribute offsets when NULLs exist in the row
484 * -Add Intimate Shared Memory(ISM) for Solaris
485 * Add documentation to lock shared memory into RAM for each OS, if possible
486 * -Use faster flex flags for performance improvement (Peter E)
487 * -Add BSD-licensed qsort() for Solaris
493 * Add use of 'const' for variables in source tree
494 * -Fix problems with libpq non-blocking/async code
495 * -Make sure all block numbers are unsigned to increase maximum table size
496 * -Merge LockMethodCtl and LockMethodTable into one shared structure (Bruce)
497 * -HOLDER/HOLDERTAB rename to PROCLOCK/PROCLOCKTAG (Bruce)
498 * -Remove LockMethodTable.prio field, not used (Bruce)
499 * Rename some /contrib modules from pg* to pg_*
500 * Move some things from /contrib into main tree
501 * Remove warnings created by -Wcast-align
502 * Move platform-specific ps status display info from ps_status.c to ports
503 * -Make one version of simple_prompt() in code (Bruce, Tom)
504 * -Compile in syslog functionaility by default (Tatsuo)
505 * Modify regression tests to prevent failures do to minor numeric rounding
506 * Add OpenBSD's getpeereid() call for local socket authentication (Bruce)
507 * Improve access-permissions check on data directory in Cygwin (Tom)
508 * -Report failure to find readline or zlib at end of configure run
509 * Add --port flag to regression tests
510 * -Increase identifier length (NAMEDATALEN) if small performance hit,
511 * -Increase maximum number of function parameters if little wasted space
512 * Add documentation for perl, including mention of DBI/DBD perl location
513 * Add optional CRC checksum to heap and index pages
514 * Change representation of whole-tuple parameters to functions
515 * Evaluate AIX cs() spinlock macro for performance optimizations (Tatsuo)
516 * Clarify use of 'application' and 'command' tags in SGML docs
517 * Better document ability to build only certain interfaces (Marc)
518 * Remove or relicense modules that are not under the BSD license, if possible
519 * Remove memory/file descriptor freeing befor elog(ERROR) (Bruce)
520 * Create native Win32 port [win32]
521 * Fix glibc's mktime() to handle pre-1970's dates
524 ---------------------------------------------------------------------------
527 Developers who have claimed items are:
528 --------------------------------------
529 * Barry is Barry Lind <barry@xythos.com>
530 * Billy is Billy G. Allie <Bill.Allie@mug.org>
531 * Bruce is Bruce Momjian <pgman@candle.pha.pa.us>
532 * Christopher is Christopher Kings-Lynne <chriskl@familyhealth.com.au>
533 * D'Arcy is D'Arcy J.M. Cain <darcy@druid.net>
534 * Dave is Dave Cramer <dave@fastcrypt.com>
535 * Edmund is Edmund Mergl <E.Mergl@bawue.de>
536 * Hiroshi is Hiroshi Inoue <Inoue@tpf.co.jp>
537 * Karel is Karel Zak <zakkr@zf.jcu.cz>
538 * Jan is Jan Wieck <wieck@sapserv.debis.de>
539 * Liam is Liam Stewart <liams@redhat.com>
540 * Marc is Marc Fournier <scrappy@hub.org>
541 * Mark is Mark Hollomon <mhh@mindspring.com>
542 * Marko is Marko Kreen <marko@l-t.ee>
543 * Michael is Michael Meskes <meskes@postgresql.org>
544 * Neil is Neil Conway <nconway@klamath.dyndns.org>
545 * Oleg is Oleg Bartunov <oleg@sai.msu.su>
546 * Peter M is Peter T Mount <peter@retep.org.uk>
547 * Peter E is Peter Eisentraut <peter_e@gmx.net>
548 * Philip is Philip Warner <pjw@rhyme.com.au>
549 * Rod is Rod Taylor <rbt@zort.ca>
550 * Ross is Ross J. Reedstrom <reedstrm@wallace.ece.rice.edu>
551 * Ryan is Ryan Bradetich <rbrad@hpb50023.boi.hp.com>
552 * Stephan is Stephan Szabo <sszabo@megazone23.bigpanda.com>
553 * Tatsuo is Tatsuo Ishii <t-ishii@sra.co.jp>
554 * Thomas is Thomas Lockhart <lockhart@fourpalms.org>
555 * Tom is Tom Lane <tgl@sss.pgh.pa.us>
556 * TomH is Tom I Helbekkmo <tih@Hamartun.Priv.no>
557 * Vadim is Vadim B. Mikheev <vadim4o@email.com>