Text Search Functions¶
get_current_ts_config()¶
Description: Gets default text search configuration.
Return type: regconfig
Example:
SELECT get_current_ts_config();
get_current_ts_config
-----------------------
english
(1 row)
length(tsvector)¶
Description: Number of lexemes in a tsvector-typed word.
Return type: integer
Example:
SELECT length('fat:2,4 cat:3 rat:5A'::tsvector);
length
--------
3
(1 row)
numnode(tsquery)¶
Description: Number of lexemes plus tsquery operators
Return type: integer
Example:
SELECT numnode('(fat & rat) | cat'::tsquery);
numnode
---------
5
(1 row)
plainto_tsquery([ config regconfig , ] query text)¶
Description: Generates tsquery lexemes without punctuation.
Return type: tsquery
Example:
SELECT plainto_tsquery('english', 'The Fat Rats');
plainto_tsquery
-----------------
'fat' & 'rat'
(1 row)
querytree(query tsquery)¶
Description: Gets indexable part of a tsquery.
Return type: text
Example:
SELECT querytree('foo & ! bar'::tsquery);
querytree
-----------
'foo'
(1 row)
setweight(tsvector, "char")¶
Description: Assigns weight to each element of tsvector.
Return type: tsvector
Example:
SELECT setweight('fat:2,4 cat:3 rat:5B'::tsvector, 'A');
setweight
-------------------------------
'cat':3A 'fat':2A,4A 'rat':5A
(1 row)
strip(tsvector)¶
Description: Removes positions and weights from tsvector.
Return type: tsvector
Example:
SELECT strip('fat:2,4 cat:3 rat:5A'::tsvector);
strip
-------------------
'cat' 'fat' 'rat'
(1 row)
to_tsquery([ config regconfig , ] query text)¶
Description: Normalizes words and converts them to tsquery.
Return type: tsquery
Example:
SELECT to_tsquery('english', 'The & Fat & Rats');
to_tsquery
---------------
'fat' & 'rat'
(1 row)
to_tsvector([ config regconfig , ] document text)¶
Description: Reduces document text to tsvector.
Return type: tsvector
Example:
SELECT to_tsvector('english', 'The Fat Rats');
to_tsvector
-----------------
'fat':2 'rat':3
(1 row)
ts_headline([ config regconfig, ] document text, query tsquery [, options text ])¶
Description: Highlights a query match.
Return type: text
Example:
SELECT ts_headline('x y z', 'z'::tsquery);
ts_headline
--------------
x y <b>z</b>
(1 row)
ts_rank([ weights float4[], ] vector tsvector, query tsquery [, normalization integer ])¶
Description: Ranks document for query.
Return type: float4
Example:
SELECT ts_rank('hello world'::tsvector, 'world'::tsquery);
ts_rank
----------
.0607927
(1 row)
ts_rank_cd([ weights float4[], ] vector tsvector, query tsquery [, normalization integer ])¶
Description: Ranks document for query using cover density.
Return type: float4
Example:
SELECT ts_rank_cd('hello world'::tsvector, 'world'::tsquery);
ts_rank_cd
------------
0
(1 row)
ts_rewrite(query tsquery, target tsquery, substitute tsquery)¶
Description: Replaces tsquery-typed word.
Return type: tsquery
Example:
SELECT ts_rewrite('a & b'::tsquery, 'a'::tsquery, 'foo|bar'::tsquery);
ts_rewrite
-------------------------
'b' & ( 'foo' | 'bar' )
(1 row)
ts_rewrite(query tsquery, select text)¶
Description: Replaces tsquery data in the target with the result of a SELECT command.
Return type: tsquery
Example:
SELECT ts_rewrite('world'::tsquery, 'select ''world''::tsquery, ''hello''::tsquery');
ts_rewrite
------------
'hello'
(1 row)