TODO list for PostgreSQL ======================== Last updated: Mon Apr 17 12:34:31 EDT 2000 Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) The most recent version of this document can be viewed at the PostgreSQL web site, http://www.PostgreSQL.org. A dash(-) marks changes that will appear in the upcoming 7.0 release. Names in brackets "[]" indicate more detailed information is available in the directory pgsql/doc/TODO.detail/ under that name. RELIABILITY ----------- PARSER * SELECT pg_class FROM pg_class generates strange error * Alter TABLE ADD COLUMN does not honor DEFAULT, add CONSTRAINT * Creating index of TIMESTAMP & RELTIME fails, or rename to DATETIME(Thomas) * SELECT foo UNION SELECT foo is incorrectly simplified to SELECT foo * Unique index on base column not honored on inserts from inherited table INSERT INTO inherit_table (unique_index_col) VALUES (dup) should fail [inherit] * Be smarter about promoting types when UNION merges different data types * redesign INSERT ... SELECT to have two levels of target list * have INTERSECT/EXCEPT prevent duplicates unless ALL is specified * SELECT DISTINCT ON col1 col1 col2 FROM tab1 is broken [distinct] * SELECT 'x'::varchar(10) INTO newtable; fails * SELECT col::DECIMAL(12,10); fails VIEWS * Views containing aggregates sometimes fail(Jan) * Creating view and inheriting the view causes view* to show duplicates(inherit) * Disallow LOCK on view MISC * Plpgsql does not handle quoted mixed-case identifiers * Buffer reference counting bugfixes * Fix libpq bug that causes it to drop backend error message sent just before connection closure (ie, any FATAL error message) * SELECT ... UNION ... ORDER BY fails when sort expr not in result list * SELECT ... UNION ... GROUP BY fails if column types disagree, no type promotion occurs * Modification of pg_class can happen while table in use by another backend. Might lead to MVCC inside of syscache * Permission to UPDATE table allows DELETE also * Some database schema's are not dumpable; do dumps in oid order ENHANCEMENTS ------------ URGENT * Add MATCH PARTIAL referential integrity * Foreign key does not check that columns referenced form a primary key or constrained by UNIQUE * Add OUTER joins, left and right[outer](Thomas, Bruce) * Allow long tuples by chaining or auto-storing outside db (TOAST)(Jan) * Fix memory leak for expressions[memory](Tom?) ADMIN * More access control over who can create tables and access the database * Test syslog functionality * Allow elog() to return error codes, not just messages * Allow international error message support and add error codes * Add ability to specifiy location of lock/socket files [flock] * Unify configuration into one configuration file TYPES * Nchar (as distinguished from ordinary varchar), * Domain capability * Add STDDEV/VARIANCE() function for standard deviation computation/variance * Allow compression of large fields or a compressed field type * Large objects o Fix large object mapping scheme, own typeid or reltype(Peter) o Not to stuff everything as files in a single directory, hash dirs o Allow large object vacuuming o Tables that start with xinv confused to be large objects * Add IPv6 capability to INET/CIDR types * Make a separate SERIAL type? * Store binary-compatible type information in the system * Add support for & operator * Allow LOCALE on a per-column basis, default to ASCII * Allow nulls in arrays * Allow arrays to be ORDER'ed * Remove Money type, add money formatting for decimal type * Declare typein/out functions in pg_proc with a special "C string" data type * Add non-large-object binary field * Functions returning sets don't really work right[function] * Make type equivalency apply to aggregates(Peter E.) VIEWS * Allow DISTINCT on views * Allow views of aggregate columns * Allow views with subselects INDEXES * Allow CREATE INDEX zman_index ON test (date_trunc( 'day', zman ) datetime_ops) fails index can't store constant parameters * Allow SQL function indexes * Add FILLFACTOR to index creation COMMANDS * ALTER TABLE ADD COLUMN to inherited table put column in wrong place [inherit] * Add ALTER TABLE DROP/ALTER COLUMN feature(Peter E) * Allow CLUSTER on all tables at once, and improve CLUSTER, loses NOT NULL specification, indexes, permissions, etc on table[cluster] * Add SIMILAR TO to allow character classes, 'pg_[a-c]%' * Auto-destroy sequence on DROP of table with SERIAL(Ryan) * Allow LOCK TABLE tab1, tab2, tab3 so all tables locked in unison * Allow INSERT/UPDATE of system-generated oid value for a row * Allow ESCAPE '\' at the end of LIKE for ANSI compliance [like] * Rewrite the LIKE handling by rewriting the user string with the supplied ESCAPE [like] * Allow RULE recompilation * Support UNION/INTERSECT/EXCEPT in sub-selects * Allow DELETE and UPDATE to use inheritance using tablename* * Allow INSERT INTO my_table VALUES (a, b, c, DEFAULT, x, y, z, ...) CLIENTS * Make NULL's come out at the beginning or end depending on the ORDER BY direction * Update reltuples from COPY command * fix array handling for ECPG * add pg_dump option to dump type names as standard ANSI types * allow psql \d to show primary and foreign keys * allow psql \d to show temporary table schema EXOTIC FEATURES * Add sql3 recursive unions * Add the concept of dataspaces * Add replication of distributed databases * Allow queries across multiple databases * Allow nested transactions MISC * Increase identifier length(NAMEDATALEN) if small performance hit * Allow row re-use without vacuum(Vadim) * Create a background process for each database that runs while database is idle, finding superceeded rows, gathering stats and vacuuming * Add UNIQUE capability to non-btree indexes * Certain indexes will not shrink, i.e. oid indexes with many inserts(Vadim) * Restore unused oid's on backend exit if no one else has gotten oids * Have UPDATE/DELETE clean out indexes * Allow cursors to be DECLAREd/OPENed/CLOSEed outside transactions * Allow DELETE WHERE CURRENT OF cursor * Transaction log, so re-do log can be on a separate disk by with after-row images(Vadim) [logging](Vadim)(in-progress) * Populate backend status area and write program to dump status data * Make oid use unsigned int more reliably, pg_atoi() * Put sort files, large objects in their own directory * Do autocommit so always in a transaction block(?) * Show location of syntax error in query [yacc] * Redesign the function call interface to handle NULLs better[function](Tom) * Missing optimizer selectivities for date, r-tree, etc. [optimizer] * Overhaul bufmgr/lockmgr/transaction manager * Add configure test to check for C++ need for *.h and namespaces * Allow BLCKSZ <= 64k, not <= 32k * redesign UNION structures to have separarate target lists * Allow multi-level query trees for INSERT INTO ... SELECT PERFORMANCE ----------- FSYNC * Allow transaction commits with rollback with no-fsync performance [fsync](Vadim) INDEXES * Use indexes in ORDER BY for min(), max() * Use index to restrict rows returned by multi-key index when used with non-consecutive keys or OR clauses, so fewer heap accesses * Improve LIMIT processing by using index to limit rows processed [limit] * Have optimizer take LIMIT into account when considering index scans [limit] * Allow SELECT * FROM tab WHERE int2col = 4 use int2col index, int8, float4, numeric/decimal too [optimizer] * Include heap CTID in btree index keys, remove equal-key cruft from btree CACHE * Cache most recent query plan(s) [prepare] * Shared catalog cache, reduce lseek()'s by caching table size in shared area MISC * Allow compression of log and meta data * Allow char() not to use variable-sized header to reduce disk size * Allow char1 data type that takes one byte of storage * Do async I/O to do better read-ahead of data * Get faster regex() code from Henry Spencer when it is available * Use mmap() rather than SYSV shared memory(?) * Make oid use oidin/oidout not int4in/int4out in pg_type.h * Improve Subplan list handling * Allow Subplans to use efficient joins(hash, merge) with upper variable [subquery] * use fmgr_info()/fmgr_faddr() instead of fmgr() calls in high-traffic places, like GROUP BY, UNIQUE, index processing, etc. * improve dynamic memory allocation by introducing tuple-context memory allocation [memory] * In WHERE tab1.x=3 AND tab1.x=tab2.y, add tab2.y=3 * Allow persistent backends [persistent] * others [performance] * prevent labels from being output for stored rules (Tom) * allow configuration of maximum number of open files SOURCE CODE ----------- * Add use of 'const' for variables in source tree * Fix C optimizer problem where fmgr_ptr calls return different types [alpha] * Does Mariposa source contain any other bug fixes? * Remove SET KSQO option if OR processing is improved(Tom) * Use macros to define NT open() file parameters, remove NT-specific defines * Change CURRENT to OLD internally for rules --------------------------------------------------------------------------- Developers who have claimed items are: -------------------------------------- * Billy is Billy G. Allie * Brook is Brook Milligan * Bruce is Bruce Momjian * Bryan is Bryan Henderson * D'Arcy is D'Arcy J.M. Cain * David is David Hartwig * Edmund is Edmund Mergl * Goran is Goran Thyni * Hiroshi is Hiroshi Inoue * Jan is Jan Wieck * Marc is Marc Fournier * Massimo Dal Zotto * Michael is Michael Meskes * Oleg is Oleg Bartunov * Peter is Peter T Mount * Peter E is Peter Eisentraut * Ryan is Ryan Bradetich * Stefan Simkovics * Tatsuo is Tatsuo Ishii * Tom is Tom Lane * Thomas is Thomas Lockhart * TomH is Tom I Helbekkmo * Vadim is "Vadim B. Mikheev"