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Place GiST and GIN text search indexes as secondary items under the main

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"index" entries for GIN/GiST.
This commit is contained in:
Bruce Momjian 2007-08-31 16:33:36 +00:00
parent 9907b2a74c
commit a8b5d6dc26
1 changed files with 34 additions and 35 deletions
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69
doc/src/sgml/textsearch.sgml
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@ -328,7 +328,7 @@ ORDER BY dlm DESC LIMIT 10;
<programlisting> <programlisting>
CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector('english', body)); CREATE INDEX pgweb_idx ON pgweb USING gin(to_tsvector('english', body));
</programlisting> </programlisting>
Notice that the 2-argument version of <function>to_tsvector</function> is Notice that the 2-argument version of <function>to_tsvector</function> is
used. Only text search functions which specify a configuration name can used. Only text search functions which specify a configuration name can
be used in expression indexes (<xref linkend="indexes-expressional">). be used in expression indexes (<xref linkend="indexes-expressional">).
@ -405,7 +405,7 @@ ORDER BY rank DESC LIMIT 10;
column current anytime <literal>title</> or <literal>body</> changes. column current anytime <literal>title</> or <literal>body</> changes.
Keep in mind that, just like with expression indexes, it is important to Keep in mind that, just like with expression indexes, it is important to
specify the configuration name when creating text search data types specify the configuration name when creating text search data types
inside triggers so the column's contents are not affected by changes to inside triggers so the column's contents are not affected by changes to
<varname>default_text_search_config</>. <varname>default_text_search_config</>.
</para> </para>
@ -448,13 +448,13 @@ SELECT to_tsvector('english', 'a fat cat sat on a mat - it ate a fat rats');
</programlisting> </programlisting>
</para> </para>
<para> <para>
In the example above we see that the resulting <type>tsvector</type> does not In the example above we see that the resulting <type>tsvector</type> does not
contain the words <literal>a</literal>, <literal>on</literal>, or contain the words <literal>a</literal>, <literal>on</literal>, or
<literal>it</literal>, the word <literal>rats</literal> became <literal>it</literal>, the word <literal>rats</literal> became
<literal>rat</literal>, and the punctuation sign <literal>-</literal> was <literal>rat</literal>, and the punctuation sign <literal>-</literal> was
ignored. ignored.
</para> </para>
<para> <para>
The <function>to_tsvector</function> function internally calls a parser The <function>to_tsvector</function> function internally calls a parser
@ -487,31 +487,31 @@ SELECT to_tsvector('english', 'a fat cat sat on a mat - it ate a fat rats');
<programlisting> <programlisting>
SELECT * FROM ts_debug('english','a fat cat sat on a mat - it ate a fat rats'); SELECT * FROM ts_debug('english','a fat cat sat on a mat - it ate a fat rats');
Alias | Description | Token | Dictionaries | Lexized token Alias | Description | Token | Dictionaries | Lexized token
-------+---------------+-------+--------------+---------------- -------+---------------+-------+--------------+----------------
lword | Latin word | a | {english} | english: {} lword | Latin word | a | {english} | english: {}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | fat | {english} | english: {fat} lword | Latin word | fat | {english} | english: {fat}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | cat | {english} | english: {cat} lword | Latin word | cat | {english} | english: {cat}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | sat | {english} | english: {sat} lword | Latin word | sat | {english} | english: {sat}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | on | {english} | english: {} lword | Latin word | on | {english} | english: {}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | a | {english} | english: {} lword | Latin word | a | {english} | english: {}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | mat | {english} | english: {mat} lword | Latin word | mat | {english} | english: {mat}
blank | Space symbols | | | blank | Space symbols | | |
blank | Space symbols | - | | blank | Space symbols | - | |
lword | Latin word | it | {english} | english: {} lword | Latin word | it | {english} | english: {}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | ate | {english} | english: {ate} lword | Latin word | ate | {english} | english: {ate}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | a | {english} | english: {} lword | Latin word | a | {english} | english: {}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | fat | {english} | english: {fat} lword | Latin word | fat | {english} | english: {fat}
blank | Space symbols | | | blank | Space symbols | | |
lword | Latin word | rats | {english} | english: {rat} lword | Latin word | rats | {english} | english: {rat}
(24 rows) (24 rows)
</programlisting> </programlisting>
@ -688,7 +688,7 @@ SELECT * FROM ts_token_type('default');
<programlisting> <programlisting>
{D-weight, C-weight, B-weight, A-weight} {D-weight, C-weight, B-weight, A-weight}
</programlisting> </programlisting>
If no weights are provided, If no weights are provided,
then these defaults are used: then these defaults are used:
@ -943,7 +943,7 @@ SELECT ts_headline('a b c', 'c'::tsquery);
a b &lt;b&gt;c&lt;/b&gt; a b &lt;b&gt;c&lt;/b&gt;
SELECT ts_headline('a b c', 'c'::tsquery, 'StartSel=&lt;,StopSel=&gt;'); SELECT ts_headline('a b c', 'c'::tsquery, 'StartSel=&lt;,StopSel=&gt;');
ts_headline ts_headline
------------- -------------
a b &lt;c&gt; a b &lt;c&gt;
</programlisting> </programlisting>
@ -989,7 +989,7 @@ ORDER BY rank DESC LIMIT 10) AS foo;
</para> </para>
<para> <para>
Some examples of normalization: Some examples of normalization:
<itemizedlist spacing="compact" mark="bullet"> <itemizedlist spacing="compact" mark="bullet">
@ -998,7 +998,7 @@ ORDER BY rank DESC LIMIT 10) AS foo;
Linguistic - ispell dictionaries try to reduce input words to a Linguistic - ispell dictionaries try to reduce input words to a
normalized form; stemmer dictionaries remove word endings normalized form; stemmer dictionaries remove word endings
</para> </para>
</listitem> </listitem>
<listitem> <listitem>
<para> <para>
Identical <acronym>URL</acronym> locations are identified and canonicalized: Identical <acronym>URL</acronym> locations are identified and canonicalized:
@ -1113,7 +1113,7 @@ SELECT ts_lexize('english_stem', 'stars');
<sect2 id="textsearch-stopwords"> <sect2 id="textsearch-stopwords">
<title>Stop Words</title> <title>Stop Words</title>
<para> <para>
Stop words are words which are very common, appear in almost Stop words are words which are very common, appear in almost
every document, and have no discrimination value. Therefore, they can be ignored every document, and have no discrimination value. Therefore, they can be ignored
@ -1207,7 +1207,7 @@ SELECT ts_lexize('public.simple_dict','The');
<programlisting> <programlisting>
SELECT * FROM ts_debug('english','Paris'); SELECT * FROM ts_debug('english','Paris');
Alias | Description | Token | Dictionaries | Lexized token Alias | Description | Token | Dictionaries | Lexized token
-------+-------------+-------+----------------+---------------------- -------+-------------+-------+----------------+----------------------
lword | Latin word | Paris | {english_stem} | english_stem: {pari} lword | Latin word | Paris | {english_stem} | english_stem: {pari}
(1 row) (1 row)
@ -1219,7 +1219,7 @@ ALTER TEXT SEARCH CONFIGURATION english
ALTER MAPPING FOR lword WITH synonym, english_stem; ALTER MAPPING FOR lword WITH synonym, english_stem;
SELECT * FROM ts_debug('english','Paris'); SELECT * FROM ts_debug('english','Paris');
Alias | Description | Token | Dictionaries | Lexized token Alias | Description | Token | Dictionaries | Lexized token
-------+-------------+-------+------------------------+------------------ -------+-------------+-------+------------------------+------------------
lword | Latin word | Paris | {synonym,english_stem} | synonym: {paris} lword | Latin word | Paris | {synonym,english_stem} | synonym: {paris}
(1 row) (1 row)
@ -1824,11 +1824,10 @@ SHOW default_text_search_config;
<secondary>GiST</secondary> <secondary>GiST</secondary>
</indexterm> </indexterm>
<!--
<indexterm zone="textsearch-indexes"> <indexterm zone="textsearch-indexes">
<primary>GiST</primary> <primary>GiST</primary>
<secondary>text search</secondary>
</indexterm> </indexterm>
-->
<term> <term>
<synopsis> <synopsis>
CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING gist(<replaceable>column</replaceable>); CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING gist(<replaceable>column</replaceable>);
@ -1851,11 +1850,11 @@ SHOW default_text_search_config;
<secondary>GIN</secondary> <secondary>GIN</secondary>
</indexterm> </indexterm>
<!--
<indexterm zone="textsearch-indexes"> <indexterm zone="textsearch-indexes">
<primary>GIN</primary> <primary>GIN</primary>
<secondary>text search</secondary>
</indexterm> </indexterm>
-->
<term> <term>
<synopsis> <synopsis>
CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING gin(<replaceable>column</replaceable>); CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> USING gin(<replaceable>column</replaceable>);
@ -2079,7 +2078,7 @@ EXPLAIN SELECT * FROM apod WHERE textsearch @@@ to_tsquery('supernovae:a');
List of fulltext configurations List of fulltext configurations
Schema | Name | Description Schema | Name | Description
----------+---------------------------- ----------+----------------------------
fulltext | fulltext_cfg | fulltext | fulltext_cfg |
public | fulltext_cfg | public | fulltext_cfg |
</programlisting> </programlisting>
</para> </para>
@ -2482,11 +2481,11 @@ dinit_intdict(PG_FUNCTION_ARGS) {
PG_FREE_IF_COPY(in, 0); PG_FREE_IF_COPY(in, 0);
pcfg=cfg; pcfg=cfg;
while (pcfg-&gt;key) while (pcfg-&gt;key)
{ {
if (strcasecmp("MAXLEN", pcfg-&gt;key) == 0) if (strcasecmp("MAXLEN", pcfg-&gt;key) == 0)
d-&gt;maxlen=atoi(pcfg-&gt;value); d-&gt;maxlen=atoi(pcfg-&gt;value);
else if ( strcasecmp("REJECTLONG", pcfg-&gt;key) == 0) else if ( strcasecmp("REJECTLONG", pcfg-&gt;key) == 0)
{ {
if ( strcasecmp("true", pcfg-&gt;value) == 0 ) if ( strcasecmp("true", pcfg-&gt;value) == 0 )
d-&gt;rejectlong=true; d-&gt;rejectlong=true;
@ -2522,7 +2521,7 @@ dlexize_intdict(PG_FUNCTION_ARGS)
if (PG_GETARG_INT32(2) &gt; d-&gt;maxlen) if (PG_GETARG_INT32(2) &gt; d-&gt;maxlen)
{ {
if (d-&gt;rejectlong) if (d-&gt;rejectlong)
{ /* stop, return void array */ { /* stop, return void array */
pfree(txt); pfree(txt);
res[0].lexeme = NULL; res[0].lexeme = NULL;
@ -2798,14 +2797,14 @@ Datum testprs_getlexeme(PG_FUNCTION_ARGS)
/* blank type */ /* blank type */
type = 12; type = 12;
/* go to the next non-white-space character */ /* go to the next non-white-space character */
while ((pst-&gt;buffer)[pst-&gt;pos] == ' ' &amp;&amp; while ((pst-&gt;buffer)[pst-&gt;pos] == ' ' &amp;&amp;
pst-&gt;pos &lt; pst-&gt;len) pst-&gt;pos &lt; pst-&gt;len)
(pst-&gt;pos)++; (pst-&gt;pos)++;
} else { } else {
/* word type */ /* word type */
type = 3; type = 3;
/* go to the next white-space character */ /* go to the next white-space character */
while ((pst-&gt;buffer)[pst-&gt;pos] != ' ' &amp;&amp; while ((pst-&gt;buffer)[pst-&gt;pos] != ' ' &amp;&amp;
pst-&gt;pos &lt; pst-&gt;len) pst-&gt;pos &lt; pst-&gt;len)
(pst-&gt;pos)++; (pst-&gt;pos)++;
} }