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73912e7fbd
Per my recent proposal(s). Null key datums can now be returned by extractValue and extractQuery functions, and will be stored in the index. Also, placeholder entries are made for indexable items that are NULL or contain no keys according to extractValue. This means that the index is now always complete, having at least one entry for every indexed heap TID, and so we can get rid of the prohibition on full-index scans. A full-index scan is implemented much the same way as partial-match scans were already: we build a bitmap representing all the TIDs found in the index, and then drive the results off that. Also, introduce a concept of a "search mode" that can be requested by extractQuery when the operator requires matching to empty items (this is just as cheap as matching to a single key) or requires a full index scan (which is not so cheap, but it sure beats failing or giving wrong answers). The behavior remains backward compatible for opclasses that don't return any null keys or request a non-default search mode. Using these features, we can now make the GIN index opclass for anyarray behave in a way that matches the actual anyarray operators for &&, <@, @>, and = ... which it failed to do before in assorted corner cases. This commit fixes the core GIN code and ginarrayprocs.c, updates the documentation, and adds some simple regression test cases for the new behaviors using the array operators. The tsearch and contrib GIN opclass support functions still need to be looked over and probably fixed. Another thing I intend to fix separately is that this is pretty inefficient for cases where more than one scan condition needs a full-index search: we'll run duplicate GinScanEntrys, each one of which builds a large bitmap. There is some existing logic to merge duplicate GinScanEntrys but it needs refactoring to make it work for entries belonging to different scan keys. Note that most of gin.h has been split out into a new file gin_private.h, so that gin.h doesn't export anything that's not supposed to be used by GIN opclasses or the rest of the backend. I did quite a bit of other code beautification work as well, mostly fixing comments and choosing more appropriate names for things.
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.
Most items can be built with `gmake all' and installed with
`gmake install' in the usual fashion, after you have run the `configure'
script in the top-level directory. Some directories supply new
user-defined functions, operators, or types. In these cases, after you have
installed the files you need to register the new entities in the database
system by running the commands in the supplied .sql file. For example,
$ psql -d dbname -f module.sql
See the PostgreSQL documentation for more information about this
procedure.
Index:
------
adminpack -
File and log manipulation routines, used by pgAdmin
by Dave Page <dpage@vale-housing.co.uk>
auth_delay
Add a short delay after a failed authentication attempt, to make
brute-force attacks on database passwords a bit harder.
by KaiGai Kohei <kaigai@ak.jp.nec.com>
auto_explain -
Log EXPLAIN output for long-running queries
by Takahiro Itagaki <itagaki.takahiro@oss.ntt.co.jp>
btree_gin -
Support for emulating BTREE indexing in GIN
by Oleg Bartunov <oleg@sai.msu.su> and Teodor Sigaev <teodor@sigaev.ru>
btree_gist -
Support for emulating BTREE indexing in GiST
by Oleg Bartunov <oleg@sai.msu.su> and Teodor Sigaev <teodor@sigaev.ru>
chkpass -
An auto-encrypted password datatype
by D'Arcy J.M. Cain <darcy@druid.net>
citext -
A case-insensitive character string datatype
by David E. Wheeler <david@kineticode.com>
cube -
Multidimensional-cube datatype (GiST indexing example)
by Gene Selkov, Jr. <selkovjr@mcs.anl.gov>
dblink -
Allows remote query execution
by Joe Conway <mail@joeconway.com>
dict_int -
Text search dictionary template for integers
by Sergey Karpov <karpov@sao.ru>
dict_xsyn -
Text search dictionary template for extended synonym processing
by Sergey Karpov <karpov@sao.ru>
earthdistance -
Functions for computing distances between two points on Earth
by Bruno Wolff III <bruno@wolff.to> and Hal Snyder <hal@vailsys.com>
fuzzystrmatch -
Levenshtein, metaphone, and soundex fuzzy string matching
by Joe Conway <mail@joeconway.com> and Joel Burton <jburton@scw.org>
hstore -
Module for storing (key, value) pairs
by Oleg Bartunov <oleg@sai.msu.su> and Teodor Sigaev <teodor@sigaev.ru>
intagg -
Integer aggregator
by mlw <markw@mohawksoft.com>
intarray -
Index support for arrays of int4, using GiST
by Teodor Sigaev <teodor@sigaev.ru> and Oleg Bartunov <oleg@sai.msu.su>
isn -
PostgreSQL type extensions for ISBN, ISSN, ISMN, EAN13 product numbers
by Germ<72>n M<>ndez Bravo (Kronuz) <kronuz@hotmail.com>
lo -
Large Object maintenance
by Peter Mount <peter@retep.org.uk>
ltree -
Tree-like data structures
by Teodor Sigaev <teodor@sigaev.ru> and Oleg Bartunov <oleg@sai.msu.su>
oid2name -
Maps numeric files to table names
by B Palmer <bpalmer@crimelabs.net>
pageinspect -
Allows inspection of database pages
Heikki Linnakangas <heikki@enterprisedb.com>
passwordcheck -
Simple password strength checker
Laurenz Albe <laurenz.albe@wien.gv.at>
pg_buffercache -
Real time queries on the shared buffer cache
by Mark Kirkwood <markir@paradise.net.nz>
pg_freespacemap -
Displays the contents of the free space map (FSM)
by Mark Kirkwood <markir@paradise.net.nz>
pg_standby -
Sample archive_command for warm standby operation
by Simon Riggs <simon@2ndquadrant.com>
pg_stat_statements -
Track statement execution times across a whole database cluster
by Takahiro Itagaki <itagaki.takahiro@oss.ntt.co.jp>
pg_trgm -
Functions for determining the similarity of text based on trigram
matching.
by Oleg Bartunov <oleg@sai.msu.su> and Teodor Sigaev <teodor@sigaev.ru>
pg_upgrade -
Support for in-place upgrade between major releases of PostgreSQL
Bruce Momjian <bruce@momjian.us> and others
pgbench -
TPC-B like benchmarking tool
by Tatsuo Ishii <ishii@sraoss.co.jp>
pgcrypto -
Cryptographic functions
by Marko Kreen <marko@l-t.ee>
pgrowlocks -
A function to return row locking information
by Tatsuo Ishii <ishii@sraoss.co.jp>
pgstattuple -
Functions to return statistics about "dead" tuples and free
space within a table
by Tatsuo Ishii <ishii@sraoss.co.jp>
seg -
Confidence-interval datatype (GiST indexing example)
by Gene Selkov, Jr. <selkovjr@mcs.anl.gov>
spi -
Various trigger functions, examples for using SPI.
sslinfo -
Functions to get information about SSL certificates
by Victor Wagner <vitus@cryptocom.ru>
start-scripts -
Scripts for starting the server at boot time on various platforms.
tablefunc -
Examples of functions returning tables
by Joe Conway <mail@joeconway.com>
test_parser -
Sample text search parser
by Sergey Karpov <karpov@sao.ru>
tsearch2 -
Compatibility package for the pre-8.3 implementation of text search.
Pavel Stehule <pavel.stehule@gmail.com>, based on code originally by
Teodor Sigaev <teodor@sigaev.ru> and Oleg Bartunov <oleg@sai.msu.su>.
unaccent -
Unaccent dictionary for text search
Teodor Sigaev <teodor@sigaev.ru> and Oleg Bartunov <oleg@sai.msu.su>.
uuid-ossp -
UUID generation functions
by Peter Eisentraut <peter_e@gmx.net>
vacuumlo -
Remove orphaned large objects
by Peter T Mount <peter@retep.org.uk>
xml2 -
Storing XML in PostgreSQL
by John Gray <jgray@azuli.co.uk>