-.gitignore
-*.swp
*.o
*.a
+*.so
*.d
*.orig
*.rej
-temp
-diffs
-etc
-results
+*.gcda
+*.gcno
+/.deps/
+/diffs/
+/results/
PG_CPPFLAGS = -DOPTIMIZE_WILDCARD_QUERY
MODULE_big = wildspeed
-OBJS = wildspeed.o
+OBJS = wildspeed.o
+
+EXTENSION = wildspeed
+DATA = wildspeed--1.0.sql
+PGFILEDESC = "Wildspeed - fast wildcard search for LIKE operator"
-DATA_built = wildspeed.sql
-DATA = uninstall_wildspeed.sql
REGRESS = wildspeed
ifdef USE_PGXS
top_builddir = ../..
include $(top_builddir)/src/Makefile.global
include $(top_srcdir)/contrib/contrib-global.mk
-endif
\ No newline at end of file
+endif
--- /dev/null
+# Wildspeed - fast wildcard search for LIKE operator
+
+Wildspeed extension provides GIN index support for wildcard search
+for LIKE operator.
+
+Online version of this document is available
+http://www.sai.msu.su/~megera/wiki/wildspeed
+
+## Authors
+
+* Oleg Bartunov <oleg@sai.msu.su>, Moscow, Moscow University, Russia
+* Teodor Sigaev <teodor@sigaev.ru>, Moscow, Moscow University,Russia
+
+## License
+
+Stable version, included into PostgreSQL distribution, released under
+BSD license. Development version, available from this site, released
+under the GNU General Public License, version 2 (June 1991)
+
+## Downloads
+
+Stable version of wildspeed is available from
+http://www.sigaev.ru/cvsweb/cvsweb.cgi/wildspeed/
+
+## Installation
+
+ % make USE_PGXS=1
+ % make install
+ % make installcheck
+ % psql DB -c 'CREATE EXTENSION wildspeed'
+
+Wildspeed provides opclass (wildcard_ops) and uses partial match
+feature of GIN, available since 8.4. Also, it supports full index scan.
+
+The size of index can be very big, since it contains entries for all
+permutations of the original word, see [1] for details. For example,
+word hello will be indexed as well as its all permutations:
+
+ =# select permute('hello');
+ permute
+ --------------------------------------
+ {hello$,ello$h,llo$he,lo$hel,o$hell}
+
+ Notice, symbol '$' is used only for visualization, in actual
+ implementation null-symbol '\0' is used.
+
+ Search query rewritten as prefix search:
+ *X -> X$*
+ X*Y -> Y$X*
+ *X* -> X*
+
+For example, search for 'hel*o' will be rewritten as 'o$hel'.
+
+Special function `permute(TEXT)`, which returns all permutations of
+argument, provided for test purposes.
+
+Performance of wildspeed depends on search pattern. Basically,
+wildspeed is less effective than btree index with text_pattern_ops for
+prefix search (the difference is greatly reduced for long prefixes) and
+much faster for wildcard search.
+
+Wildspeed by default uses optimization (skip short patterns if there
+are long one), which can be turned off in Makefile by removing define
+`-DOPTIMIZE_WILDCARD_QUERY`.
+
+## References
+
+* http://www.cs.wright.edu/~tkprasad/courses/cs499/L05TolerantIR.ppt
+* http://nlp.stanford.edu/IR-book/html/htmledition/permuterm-indexes-1.html
+
+## Examples
+
+Table words contains 747358 records, w1 and w2 columns contains the
+same data in order to test performance of Btree (w1) and GIN (w2)
+indexes:
+
+ Table "public.words"
+ Column | Type | Modifiers
+ --------+------+-----------
+ w1 | text |
+ w2 | text |
+
+ words=# create index bt_idx on words using btree (w1 text_pattern_ops);
+ CREATE INDEX
+ Time: 1885.195 ms
+ words=# create index gin_idx on words using gin (w2 wildcard_ops);
+ vacuum analyze;
+ CREATE INDEX
+ Time: 530351.223 ms
+
+Size:
+
+ words=# select pg_relation_size('words');
+ pg_relation_size
+ ------------------
+ 43253760
+
+ words=# select pg_relation_size('gin_idx');
+ pg_relation_size
+ ------------------
+ 417816576
+ (1 row)
+
+ words=# select pg_relation_size('bt_idx');
+ pg_relation_size
+ ------------------
+ 23437312
+ (1 row)
+
+ Prefix search:
+ words=# select count(*) from words where w1 like 'a%';
+ count
+ -------
+ 15491
+ (1 row)
+
+ Time: 7.502 ms
+ words=# select count(*) from words where w2 like 'a%';
+ count
+ -------
+ 15491
+ (1 row)
+
+ Time: 31.152 ms
+
+Wildcard search:
+
+ words=# select count(*) from words where w1 like '%asd%';
+ count
+ -------
+ 26
+ (1 row)
+
+ Time: 147.308 ms
+ words=# select count(*) from words where w2 like '%asd%';
+ count
+ -------
+ 26
+ (1 row)
+
+ Time: 0.339 ms
+
+Full index scan:
+
+ words=# set enable_seqscan to off;
+ words=# explain analyze select count(*) from words where w2 like '%';
+ QUERY PLAN
+
+ --------------------------------------------------------------------------------------------------------------
+ -----------------------------
+ Aggregate (cost=226274.98..226274.99 rows=1 width=0) (actual time=2218.709..2218.709 rows=1 loops=1)
+ -> Bitmap Heap Scan on words (cost=209785.73..224406.77 rows=747283 width=0) (actual time=1510.516..1913.
+ 430 rows=747358 loops=1)
+ Filter: (w2 ~~ '%'::text)
+ -> Bitmap Index Scan on gin_idx (cost=0.00..209598.91 rows=747283 width=0) (actual time=1509.358..1
+ 509.358 rows=747358 loops=1)
+ Index Cond: (w2 ~~ '%'::text)
+ Total runtime: 2218.747 ms
+ (6 rows)
+++ /dev/null
-WildSpeed - fast wildcard search for LIKE operator
-
- Wildspeed extension provides GIN index support for wildcard search
- for LIKE operator.
-
- Online version of this document is available
- http://www.sai.msu.su/~megera/wiki/wildspeed
-
-Authors
-
- * Oleg Bartunov <oleg@sai.msu.su>, Moscow, Moscow University, Russia
- * Teodor Sigaev <teodor@sigaev.ru>, Moscow, Moscow University,Russia
-
-License
-
- Stable version, included into PostgreSQL distribution, released under
- BSD license. Development version, available from this site, released
- under the GNU General Public License, version 2 (June 1991)
-
-Downloads
-
- Stable version of wildspeed is available from
- http://www.sigaev.ru/cvsweb/cvsweb.cgi/wildspeed/
-
-Installation
-
-% cd PGSQLSRC/contrib
-% tar xzvf wildspeed.tar.gz
-% make
-% make install
-% make installcheck
-% psql DB < wildspeed.sql
-
- Wildspeed provides opclass (wildcard_ops) and uses partial match
- feature of GIN, available since 8.4. Also, it supports full index scan.
-
- The size of index can be very big, since it contains entries for all
- permutations of the original word, see [1] for details. For example,
- word hello will be indexed as well as its all permutations:
-=# select permute('hello');
- permute
---------------------------------------
- {hello$,ello$h,llo$he,lo$hel,o$hell}
-
- Notice, symbol '$' is used only for visualization, in actual
- implementation null-symbol '\0' is used.
-
- Search query rewritten as prefix search:
-*X -> X$*
-X*Y -> Y$X*
-*X* -> X*
-
- For example, search for 'hel*o' will be rewritten as 'o$hel'.
-
- Special function permute(TEXT), which returns all permutations of
- argument, provided for test purposes.
-
- Performance of wildspeed depends on search pattern. Basically,
- wildspeed is less effective than btree index with text_pattern_ops for
- prefix search (the difference is greatly reduced for long prefixes) and
- much faster for wildcard search.
-
- Wildspeed by default uses optimization (skip short patterns if there
- are long one), which can be turned off in Makefile by removing define
- -DOPTIMIZE_WILDCARD_QUERY.
-
-References
-
- 1. http://www.cs.wright.edu/~tkprasad/courses/cs499/L05TolerantIR.ppt, see also,
- http://nlp.stanford.edu/IR-book/html/htmledition/permuterm-indexes-1.html
-
-Examples
-
- Table words contains 747358 records, w1 and w2 columns contains the
- same data in order to test performance of Btree (w1) and GIN (w2)
- indexes:
- Table "public.words"
- Column | Type | Modifiers
---------+------+-----------
- w1 | text |
- w2 | text |
-
-words=# create index bt_idx on words using btree (w1 text_pattern_ops);
-CREATE INDEX
-Time: 1885.195 ms
-words=# create index gin_idx on words using gin (w2 wildcard_ops);
-vacuum analyze;
-CREATE INDEX
-Time: 530351.223 ms
-
-Size:
-
-words=# select pg_relation_size('words');
- pg_relation_size
-------------------
- 43253760
-
-words=# select pg_relation_size('gin_idx');
- pg_relation_size
-------------------
- 417816576
-(1 row)
-
-words=# select pg_relation_size('bt_idx');
- pg_relation_size
-------------------
- 23437312
-(1 row)
-
- Prefix search:
-words=# select count(*) from words where w1 like 'a%';
- count
--------
- 15491
-(1 row)
-
-Time: 7.502 ms
-words=# select count(*) from words where w2 like 'a%';
- count
--------
- 15491
-(1 row)
-
-Time: 31.152 ms
-
- Wildcard search:
-words=# select count(*) from words where w1 like '%asd%';
- count
--------
- 26
-(1 row)
-
-Time: 147.308 ms
-words=# select count(*) from words where w2 like '%asd%';
- count
--------
- 26
-(1 row)
-
-Time: 0.339 ms
-
- Full index scan:
-words=# set enable_seqscan to off;
-words=# explain analyze select count(*) from words where w2 like '%';
- QUERY PLAN
-
---------------------------------------------------------------------------------------------------------------
------------------------------
- Aggregate (cost=226274.98..226274.99 rows=1 width=0) (actual time=2218.709..2218.709 rows=1 loops=1)
- -> Bitmap Heap Scan on words (cost=209785.73..224406.77 rows=747283 width=0) (actual time=1510.516..1913.
-430 rows=747358 loops=1)
- Filter: (w2 ~~ '%'::text)
- -> Bitmap Index Scan on gin_idx (cost=0.00..209598.91 rows=747283 width=0) (actual time=1509.358..1
-509.358 rows=747358 loops=1)
- Index Cond: (w2 ~~ '%'::text)
- Total runtime: 2218.747 ms
-(6 rows)
-
--
-- first, define the datatype. Turn off echoing so that expected file
--- does not depend on contents of wildspeed.sql.
+-- does not depend on `CREATE EXTENSION wildspeed` output.
--
SET client_min_messages = warning;
\set ECHO none
--
-- first, define the datatype. Turn off echoing so that expected file
--- does not depend on contents of wildspeed.sql.
+-- does not depend on `CREATE EXTENSION wildspeed` output.
--
SET client_min_messages = warning;
\set ECHO none
-\i wildspeed.sql
+CREATE EXTENSION wildspeed;
\set ECHO all
RESET client_min_messages;
+++ /dev/null
-BEGIN;
-
-DROP FUNCTION IF EXISTS permute(text) CASCADE;
-DROP OPERATOR CLASS IF EXISTS wildcard_ops USING gin CASCADE;
-DROP FUNCTION IF EXISTS gin_extract_permuted(text, internal) CASCADE;
-DROP FUNCTION IF EXISTS wildcmp(text, text, bool) CASCADE;
-DROP FUNCTION IF EXISTS gin_extract_wildcard(text, internal, int2, internal) CASCADE;
-DROP FUNCTION IF EXISTS gin_consistent_wildcard(internal, int2, text) CASCADE;
-
-END;
-BEGIN;
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "CREATE EXTENSION wildspeed" to load this file. \quit
-- support functions for gin
CREATE OR REPLACE FUNCTION gin_extract_permuted(text, internal)
CREATE OPERATOR CLASS wildcard_ops
FOR TYPE text USING gin
AS
- OPERATOR 1 ~~,
+ OPERATOR 1 ~~,
FUNCTION 1 wildcmp(text,text),
FUNCTION 2 gin_extract_permuted(text, internal),
FUNCTION 3 gin_extract_wildcard(text, internal, int2, internal),
RETURNS _text
AS 'MODULE_PATHNAME'
LANGUAGE C STRICT IMMUTABLE;
-
-COMMIT;
--- /dev/null
+# wildspeed extension
+comment = 'Wildspeed - fast wildcard search for LIKE operator'
+default_version = '1.0'
+module_pathname = '$libdir/wildspeed'
+relocatable = true
projects / wildspeed.git / commitdiff