postgresql/contrib
Andrew Gierth b5635948ab Support hashed aggregation with grouping sets.
This extends the Aggregate node with two new features: HashAggregate
can now run multiple hashtables concurrently, and a new strategy
MixedAggregate populates hashtables while doing sorted grouping.

The planner will now attempt to save as many sorts as possible when
planning grouping sets queries, while not exceeding work_mem for the
estimated combined sizes of all hashtables used.  No SQL-level changes
are required.  There should be no user-visible impact other than the
new EXPLAIN output and possible changes to result ordering when ORDER
BY was not used (which affected a few regression tests).  The
enable_hashagg option is respected.

Author: Andrew Gierth
Reviewers: Mark Dilger, Andres Freund
Discussion: https://postgr.es/m/87vatszyhj.fsf@news-spur.riddles.org.uk
2017-03-27 04:20:54 +01:00
..
adminpack Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
amcheck amcheck: Harden tests against concurrent autovacuums. 2017-03-14 13:07:38 -07:00
auth_delay Consistently declare timestamp variables as TimestampTz. 2017-02-23 15:57:08 -05:00
auto_explain Allow for parallel execution whenever ExecutorRun() is done only once. 2017-03-23 13:14:36 -04:00
bloom Add optimizer and executor support for parallel index scans. 2017-02-15 13:53:24 -05:00
btree_gin Add btree_gin support for enum types 2017-03-21 11:04:17 -04:00
btree_gist Add btree_gist support for enum types. 2017-03-21 10:43:27 -04:00
chkpass Further cleanup from the strong-random patch. 2016-12-12 11:55:32 +02:00
citext Move some things from builtins.h to new header files 2017-01-20 20:29:53 -05:00
cube Fix typos in comments. 2017-02-06 11:33:58 +02:00
dblink Fix compiler warning 2017-03-13 15:44:50 -04:00
dict_int Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
dict_xsyn Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
earthdistance Fix typos in comments. 2017-02-06 11:33:58 +02:00
file_fdw Logical replication support for initial data copy 2017-03-23 08:55:37 -04:00
fuzzystrmatch Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
hstore Assume deconstruct_array() outputs are untoasted. 2017-03-12 19:35:31 -04:00
hstore_plperl Code review for avoidance of direct cross-module links. 2017-02-02 11:21:16 -05:00
hstore_plpython Drop support for Python 2.3 2017-02-21 09:49:22 -05:00
intagg Schema-qualify some references to regprocedure. 2016-06-10 10:41:58 -04:00
intarray Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
isn Fix typos in comments. 2017-02-06 11:33:58 +02:00
lo Move atooid() definition to a central place 2017-03-01 11:55:28 -05:00
ltree Spelling fixes 2017-03-14 12:58:39 -04:00
ltree_plpython Code review for avoidance of direct cross-module links. 2017-02-02 11:21:16 -05:00
oid2name Fix hard-coded relkind constants in assorted other files. 2017-03-09 23:36:52 -05:00
pageinspect pageinspect: Add page_checksum function 2017-03-17 10:55:17 -04:00
passwordcheck Replace isMD5() with a more future-proof way to check if pw is encrypted. 2017-02-01 13:11:37 +02:00
pg_buffercache Don't bother to lock bufmgr partitions in pg_buffercache. 2016-09-29 13:16:30 +03:00
pg_freespacemap Update pg_freespacemap extension for parallel query. 2016-06-09 17:18:16 -04:00
pg_prewarm Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
pg_standby Fix typos in comments. 2017-02-06 11:33:58 +02:00
pg_stat_statements Allow for parallel execution whenever ExecutorRun() is done only once. 2017-03-23 13:14:36 -04:00
pg_trgm Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
pg_visibility Refactor GetOldestXmin() to use flags 2017-03-22 16:51:01 +00:00
pgcrypto Spelling fixes in code comments 2017-03-14 12:58:39 -04:00
pgrowlocks Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
pgstattuple Refactor GetOldestXmin() to use flags 2017-03-22 16:51:01 +00:00
postgres_fdw Support hashed aggregation with grouping sets. 2017-03-27 04:20:54 +01:00
seg Fix typos in comments. 2017-02-06 11:33:58 +02:00
sepgsql Blindly attempt to fix sepgsql tests #2. 2017-03-25 20:54:23 -07:00
spi Spelling fixes in code comments 2017-03-14 12:58:39 -04:00
sslinfo Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
start-scripts Fix typos in comments. 2017-02-06 11:33:58 +02:00
tablefunc Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
tcn Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
test_decoding Improve isolation tests infrastructure. 2017-03-14 15:56:17 -07:00
tsm_system_rows Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
tsm_system_time Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
unaccent Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
uuid-ossp Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
vacuumlo Fix hard-coded relkind constants in assorted other files. 2017-03-09 23:36:52 -05:00
xml2 Use wrappers of PG_DETOAST_DATUM_PACKED() more. 2017-03-12 19:35:34 -04:00
Makefile Add amcheck extension to contrib. 2017-03-09 16:33:02 -08:00
README Rename 'gmake' to 'make' in docs and recommended commands 2014-02-12 17:29:19 -05:00
contrib-global.mk Respect TEMP_CONFIG when pg_regress_check and friends are called 2016-02-27 12:28:21 -05:00

README

The PostgreSQL contrib tree
---------------------------

This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
because they address a limited audience or are too experimental to be
part of the main source tree.  This does not preclude their
usefulness.

User documentation for each module appears in the main SGML
documentation.

When building from the source distribution, these modules are not
built automatically, unless you build the "world" target.  You can
also build and install them all by running "make all" and "make
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.

Some directories supply new user-defined functions, operators, or
types.  To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command.  In a fresh database,
you can simply do

    CREATE EXTENSION module_name;

See the PostgreSQL documentation for more information about this
procedure.