1 TODO list for PostgreSQL
2 ========================
3 Last updated: Fri Feb 14 12:02:42 EST 2003
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 7.4 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
29 * Create native Win32 port [win32]
35 * Allow elog() to return error codes, module name, file name, line
36 number, not just messages (Peter E)
37 * Add error codes (Peter E)
38 * Make error messages more consistent [error]
39 * Show location of syntax error in query [yacc]
46 * Remove unreferenced table files and temp tables during database vacuum
47 or postmaster startup (Bruce)
48 * Remove behavior of postmaster -o after making postmaster/postgres
50 * Allow easy display of usernames in a group
51 * Allow configuration files to be specified in a different directory
52 * Add start time to pg_stat_activity
53 * Allow limits on per-db/user connections
54 * Have standalone backend read postgresql.conf
55 * Add group object ownership, so groups can rename/drop/grant on objects,
56 so we can implement roles
57 * Add the concept of dataspaces/tablespaces [tablespaces]
58 * Allow incremental backups
64 * Add IPv6 capability to INET/CIDR types
65 * Remove Money type, add money formatting for decimal type
66 * Change factorial to return a numeric
67 * Change NUMERIC data type to use base 10,000 internally
68 * Change NUMERIC to enforce the maximum precision, and increase it
69 * Add function to return compressed length of TOAST data values (Tom)
70 * Allow INET subnet tests using non-constants
71 * Add now("transaction|statement|clock") functionality
72 * -Add GUC variables to control floating number output digits (Pedro Ferreira)
73 * Have sequence dependency track use of DEFAULT sequences, seqname.nextval
74 * Disallow changing default expression of a SERIAL column
75 * Allow infinite dates just like infinite timestamps
79 o Allow better handling of numeric constants, type conversion
83 o Allow nulls in arrays
84 o Allow arrays to be ORDER'ed
85 o Support construction of array result values in expressions
88 o Improve vacuum of large objects, like /contrib/vacuumlo
89 o Add security checking for large objects
90 o Make file in/out interface for TOAST columns, similar to large object
91 interface (force out-of-line storage and no compression)
92 o Auto-delete large objects when referencing row is deleted
95 Multi-Language Support
96 ======================
98 * Add NCHAR (as distinguished from ordinary varchar),
99 * Allow LOCALE on a per-column basis, default to ASCII
100 * Support multiple simultaneous character sets, per SQL92
101 * Improve Unicode combined character handling
102 * Optimize locale to have minimal performance impact when not used (Peter E)
103 * Add octet_length_server() and octet_length_client() (Thomas, Tatsuo)
104 * Make octet_length_client the same as octet_length() (?)
105 * Prevent mismatch of frontend/backend encodings from converting bytea
106 data from being interpreted as encoded strings
107 * Remove Cyrillic recode support
113 * Automatically create rules on views so they are updateable, per SQL92 [view]
114 * Add the functionality for WITH CHECK OPTION clause of CREATE VIEW
115 * Allow NOTIFY in rules involving conditionals
116 * Have views on temporary tables exist in the temporary namespace
117 * Move psql backslash information into views
118 * Allow RULE recompilation
124 * Allow CREATE INDEX zman_index ON test (date_trunc( 'day', zman ) datetime_ops)
125 fails index can't store constant parameters
126 * Order duplicate index entries by tid for faster heap lookups
127 * Allow inherited tables to inherit index, UNIQUE constraint, and primary
128 key, foreign key [inheritance]
129 * UNIQUE INDEX on base column not honored on inserts from inherited table
130 INSERT INTO inherit_table (unique_index_col) VALUES (dup) should fail
132 * Add UNIQUE capability to non-btree indexes
133 * Add btree index support for reltime, tinterval, regproc
134 * Add rtree index support for line, lseg, path, point
135 * Certain indexes will not shrink, e.g. indexes on ever-increasing
136 columns and indexes with many duplicate keys
137 * Use indexes for min() and max() or convert to SELECT col FROM tab ORDER
138 BY col DESC LIMIT 1 if appropriate index exists and WHERE clause acceptible
139 * Allow LIKE indexing optimization for non-ASCII locales
140 * Use index to restrict rows returned by multi-key index when used with
141 non-consecutive keys or OR clauses, so fewer heap accesses
142 * Be smarter about insertion of already-ordered data into btree index
143 * Prevent index uniqueness checks when UPDATE does not modifying column
144 * Use bitmaps to fetch heap pages in sequential order [performance]
145 * Use bitmaps to combine existing indexes [performance]
146 * Improve handling of index scans for NULL
147 * Allow SELECT * FROM tab WHERE int2col = 4 to use int2col index, int8,
148 float4, numeric/decimal too [optimizer]
149 * Add FILLFACTOR to btree index creation
150 * Add concurrency to GIST
151 * Improve concurrency of hash indexes (Neil)
157 * Add BETWEEN ASYMMETRIC/SYMMETRIC (Christopher)
158 * Allow LIMIT/OFFSET to use expressions
159 * CREATE TABLE AS can not determine column lengths from expressions [atttypmod]
160 * Allow UPDATE to handle complex aggregates [update]
161 * Allow command blocks to ignore certain types of errors
162 * Allow backslash handling in quoted strings to be disabled for portability
163 * Return proper effected tuple count from complex commands [return]
164 * Allow DELETE to handle table aliases for self-joins [delete]
165 * Add CORRESPONDING BY to UNION/INTERSECT/EXCEPT
166 * Allow REINDEX to rebuild all indexes, remove /contrib/reindex
167 * Make a transaction-safe TRUNCATE
168 * Add ROLLUP, CUBE, GROUPING SETS options to GROUP BY
169 * Add schema option to createlang
173 o ALTER TABLE ADD COLUMN does not honor DEFAULT and non-CHECK CONSTRAINT
174 o ALTER TABLE ADD COLUMN column DEFAULT should fill existing
175 rows with DEFAULT value
176 o ALTER TABLE ADD COLUMN column SERIAL doesn't create sequence because
178 o Add ALTER TABLE tab SET WITHOUT OIDS
179 * Add ALTER SEQUENCE to modify min/max/increment/cache/cycle values
182 o Automatically maintain clustering on a table
183 o Allow CLUSTER to cluster all tables, remove clusterdb
186 o Allow dump/load of CSV format
187 o Allow COPY to report error lines and continue; optionally
188 allow error codes to be specified; requires savepoints or can
189 not be run in a multi-statement transaction
190 o Allow copy to understand \x as hex
193 o Allow BINARY option to SELECT, just like DECLARE
194 o -MOVE 0 should not move to end of cursor (Bruce)
195 o Allow UPDATE/DELETE WHERE CURRENT OF cursor using per-cursor tid
196 stored in the backend
197 o Prevent DROP of table being referenced by our own open cursor
198 o Allow cursors outside transactions [cursor]
201 o Allow INSERT/UPDATE of system-generated oid value for a row
202 o Allow INSERT INTO tab (col1, ..) VALUES (val1, ..), (val2, ..)
203 o Allow INSERT/UPDATE ... RETURNING new.col or old.col; handle
207 o Add SET PERFORMANCE_TIPS option to suggest INDEX, VACUUM, VACUUM
210 o Allow EXPLAIN EXECUTE to see prepared plans
211 o Allow SHOW of non-modifiable variables, like pg_controldata
212 o Add GUC parameter to control the maximum number of rewrite cycles
214 * SERVER-SIDE LANGUAGES
215 o Allow PL/PgSQL's RAISE function to take expressions
216 o Change PL/PgSQL to use palloc() instead of malloc()
217 o Add untrusted version of plpython
218 o Allow Java server-side programming, http://pljava.sourceforge.net
220 o Fix problems with complex temporary table creation/destruction
221 without using PL/PgSQL EXECUTE, needs cache prevention/invalidation
222 o Fix PL/pgSQL RENAME to work on variables other than OLD/NEW
223 o Improve PL/PgSQL exception handling
224 o Allow parameters to be specified by name and type during
226 o Allow function parameters to be passed by name,
227 get_employee_salary(emp_id => 12345, tax_year => 2001)
228 o Add PL/PgSQL packages
229 o Allow array declarations and other data types in PL/PgSQL DECLARE
230 o Add PL/PgSQL PROCEDURES that can return multiple values
231 o Add table function support to pltcl, plperl, plpython
232 o Make PL/PgSQL %TYPE schema-aware
233 o Allow PL/PgSQL to support array element assignment
239 * Allow psql to show transaction status if backend protocol changes made
240 * Add XML interface: psql, pg_dump, COPY, separate server (?)
241 * -Add schema, cast, and conversion backslash commands to psql (Christopher)
242 * Allow pg_dump to dump a specific schema
243 * Allow psql to do table completion for SELECT * FROM schema_part and
244 table completion for SELECT * FROM schema_name.
247 o Comprehensive test suite. This may be available already.
248 o JDBC-standard BLOB support
249 o Error Codes (pending backend implementation)
250 o Support both 'make' and 'ant'
251 o Fix LargeObject API to handle OIDs as unsigned ints
252 o Use cursors implicitly to avoid large results (see setCursorName())
253 o Add LISTEN/NOTIFY support to the JDBC driver (Barry)
256 o Implement set descriptor, using descriptor
257 o Make casts work in variable initializations
259 o Allow multi-threaded use of SQLCA
260 o Solve cardinality > 1 for input descriptors / variables
261 o Understand structure definitions outside a declare section
262 o sqlwarn[6] should be 'W' if the PRECISION or SCALE value specified
263 o Improve error handling
264 o Allow :var[:index] or :var[<integer>] as cvariable for an array var
265 o Add a semantic check level, e.g. check if a table really exists
266 o Fix nested C comments
268 o fix handling of DB attributes that are arrays
271 o Allow users to register their own types with _pg
272 o Allow SELECT to return a dictionary of dictionaries
273 o Allow COPY BINARY FROM
276 Referential Integrity
277 =====================
279 * Add MATCH PARTIAL referential integrity [foreign]
280 * Add deferred trigger queue file (Jan)
281 * Implement dirty reads and use them in RI triggers
282 * Enforce referential integrity for system tables
283 * Change foreign key constraint for array -> element to mean element
285 * Allow DEFERRABLE UNIQUE constraints
286 * Allow triggers to be disabled [trigger]
287 * -Support statement-level triggers (Neil)
288 * Support triggers on columns (Neil)
294 * Flush cached query plans when their underlying catalog data changes
295 * Use dependency information to dump data in proper order
301 * Overhaul bufmgr/lockmgr/transaction manager
302 * Allow savepoints / nested transactions [transactions] (Bruce)
308 * Add SQL99 WITH clause to SELECT (Tom, Fernando)
309 * Add SQL99 WITH RECURSIVE to SELECT (Tom, Fernando)
310 * Allow queries across multiple databases [crossdb]
311 * Add pre-parsing phase that converts non-ANSI features to supported features
312 * Allow plug-in modules to emulate features from other databases
313 * SQL*Net listener that makes PostgreSQL appear as an Oracle database
315 * Two-phase commit to implement distributed transactions
325 * Delay fsync() when other backends are about to commit too [fsync]
326 o Determine optimal commit_delay value
327 * Determine optimal fdatasync/fsync, O_SYNC/O_DSYNC options
328 o Allow multiple blocks to be written to WAL with one write()
333 * Shared catalog cache, reduce lseek()'s by caching table size in shared area
334 * Add free-behind capability for large sequential scans (Bruce)
335 * Allow binding query args over FE/BE protocol
336 * Consider use of open/fcntl(O_DIRECT) to minimize OS caching
337 * Make blind writes go through the file descriptor cache
338 * Cache last known per-tuple offsets to speed long tuple access
344 * Improve speed with indexes (perhaps recreate index instead) [vacuum]
345 * Reduce lock time by moving tuples with read lock, then write
346 lock and truncate table [vacuum]
347 * Provide automatic running of vacuum in the background (Tom) [vacuum]
348 * Allow free space map to be auto-sized or warn when it is too small
354 * Make locking of shared data structures more fine-grained
355 * Add code to detect an SMP machine and handle spinlocks accordingly
356 from distributted.net, http://www1.distributed.net/source,
357 in client/common/cpucheck.cpp
358 * Research use of sched_yield() for spinlock acquisition failure
364 * Experiment with multi-threaded backend [thread]
365 * Add connection pooling [pool]
366 * Allow persistent backends [persistent]
367 * Create a transaction processor to aid in persistent connections and
369 * Do listen() in postmaster and accept() in pre-forked backend
370 * Have pre-forked backend pre-connect to last requested database or pass
371 file descriptor to backend pre-forked for matching database
377 * Have after-change WAL write()'s write only modified data to kernel
378 * Reduce number of after-change WAL writes; they exist only to gaurd against
379 partial page writes [wal]
380 * Turn off after-change writes if fsync is disabled (?)
381 * Add WAL index reliability improvement to non-btree indexes
382 * Find proper defaults for postgresql.conf WAL entries
383 * Add checkpoint_min_warning postgresql.conf option to warn about checkpoints
384 that are too frequent
385 * Allow xlog directory location to be specified during initdb, perhaps
387 * Allow pg_xlog to be moved without symlinks
393 * Improve Subplan list handling
394 * Allow Subplans to use efficient joins(hash, merge) with upper variable
395 * -Add hash for evaluating GROUP BY aggregates (Tom)
396 * Allow merge and hash joins on expressions not just simple variables (Tom)
397 * Make IN/NOT IN have similar performance to EXISTS/NOT EXISTS [exists]
398 * Missing optimizer selectivities for date, r-tree, etc. [optimizer]
399 * Allow ORDER BY ... LIMIT to select top values without sort or index
400 using a sequential scan for highest/lowest values (Oleg)
401 * -Inline simple SQL functions to avoid overhead (Tom)
402 * Precompile SQL functions to avoid overhead (Neil)
403 * Add utility to compute accurate random_page_cost value
404 * Improve ability to display optimizer analysis using OPTIMIZER_DEBUG
405 * Use CHECK constraints to improve optimizer decisions
406 * Check GUC geqo_threshold to see if it is still accurate
407 * Allow sorting, temp files, temp tables to use multiple work directories
413 * Do async I/O for faster random read-ahead of data
414 * -Get faster regex() code from Henry Spencer <henry@zoo.utoronto.ca>
415 * Use mmap() rather than SYSV shared memory or to write WAL files (?) [mmap]
416 * Improve caching of attribute offsets when NULLs exist in the row
418 * Wire Protocol Changes
419 o Show transaction status in psql
420 o Allow binding of query parameters, support for prepared queries
421 o Add optional textual message to NOTIFY
422 o Remove hard-coded limits on user/db/password names
423 o Remove unused elements of startup packet (unused, tty, passlength)
424 o Fix COPY/fastpath protocol?
425 o Allow fastpast to pass values in portable format
426 o Replication support?
428 o Dynamic character set handling
429 o Special passing of binary values in platform-neutral format (bytea?)
431 o Add decoded type, length, precision
438 * Add use of 'const' for variables in source tree
439 * Rename some /contrib modules from pg* to pg_*
440 * Move some things from /contrib into main tree
441 * Remove warnings created by -Wcast-align
442 * Move platform-specific ps status display info from ps_status.c to ports
443 * Modify regression tests to prevent failures do to minor numeric rounding
444 * -Add OpenBSD's getpeereid() call for local socket authentication
445 * Improve access-permissions check on data directory in Cygwin (Tom)
446 * Add --port flag to regression tests
447 * Add documentation for perl, including mention of DBI/DBD perl location
448 * Add optional CRC checksum to heap and index pages
449 * Change representation of whole-tuple parameters to functions
450 * Clarify use of 'application' and 'command' tags in SGML docs
451 * Better document ability to build only certain interfaces (Marc)
452 * Remove or relicense modules that are not under the BSD license, if possible
453 * Remove memory/file descriptor freeing befor elog(ERROR) (Bruce)
454 * Acquire lock on a relation before building a relcache entry for it
455 * Research interaction of setitimer() and sleep() used by statement_timeout
457 ---------------------------------------------------------------------------
460 Developers who have claimed items are:
461 --------------------------------------
462 * Barry is Barry Lind <barry@xythos.com>
463 * Billy is Billy G. Allie <Bill.Allie@mug.org>
464 * Bruce is Bruce Momjian <pgman@candle.pha.pa.us> of Software Research Assoc.
465 * Christopher is Christopher Kings-Lynne <chriskl@familyhealth.com.au> of
466 Family Health Network
467 * D'Arcy is D'Arcy J.M. Cain <darcy@druid.net> of The Cain Gang Ltd.
468 * Dave is Dave Cramer <dave@fastcrypt.com>
469 * Edmund is Edmund Mergl <E.Mergl@bawue.de>
470 * Fernando Nasser <fnasser@redhat.com> of Red Hat
471 * Gavin Sherry <swm@linuxworld.com.au> of Alcove Systems Engineering
472 * Hiroshi is Hiroshi Inoue <Inoue@tpf.co.jp>
473 * Karel is Karel Zak <zakkr@zf.jcu.cz>
474 * Jan is Jan Wieck <JanWieck@Yahoo.com> of PeerDirect Corp.
475 * Liam is Liam Stewart <liams@redhat.com> of Red Hat
476 * Marc is Marc Fournier <scrappy@hub.org> of PostgreSQL, Inc.
477 * Mark is Mark Hollomon <mhh@mindspring.com>
478 * Michael is Michael Meskes <meskes@postgresql.org> of Credativ
479 * Neil is Neil Conway <neilc@samurai.com>
480 * Oleg is Oleg Bartunov <oleg@sai.msu.su>
481 * Peter M is Peter T Mount <peter@retep.org.uk> of Retep Software
482 * Peter E is Peter Eisentraut <peter_e@gmx.net>
483 * Philip is Philip Warner <pjw@rhyme.com.au> of Albatross Consulting Pty. Ltd.
484 * Rod is Rod Taylor <rbt@zort.ca>
485 * Ross is Ross J. Reedstrom <reedstrm@wallace.ece.rice.edu>
486 * Stephan is Stephan Szabo <sszabo@megazone23.bigpanda.com>
487 * Tatsuo is Tatsuo Ishii <t-ishii@sra.co.jp> of Software Research Assoc.
488 * Thomas is Thomas Lockhart <lockhart@fourpalms.org> of Jet Propulsion Labratory
489 * Tom is Tom Lane <tgl@sss.pgh.pa.us> of Red Hat
490 * Vadim is Vadim B. Mikheev <vadim4o@email.com> of Sector Data