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Consistently uppercase index method names, e.g. GIN, and add space after the index method name and the parentheses enclosing the column names.
59 lines
1.8 KiB
Plaintext
59 lines
1.8 KiB
Plaintext
<!-- doc/src/sgml/btree-gin.sgml -->
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<sect1 id="btree-gin" xreflabel="btree_gin">
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<title>btree_gin</title>
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<indexterm zone="btree-gin">
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<primary>btree_gin</primary>
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</indexterm>
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<para>
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<filename>btree_gin</> provides sample GIN operator classes that
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implement B-tree equivalent behavior for the data types
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<type>int2</>, <type>int4</>, <type>int8</>, <type>float4</>,
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<type>float8</>, <type>timestamp with time zone</>,
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<type>timestamp without time zone</>, <type>time with time zone</>,
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<type>time without time zone</>, <type>date</>, <type>interval</>,
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<type>oid</>, <type>money</>, <type>"char"</>,
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<type>varchar</>, <type>text</>, <type>bytea</>, <type>bit</>,
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<type>varbit</>, <type>macaddr</>, <type>inet</>, and <type>cidr</>.
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</para>
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<para>
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In general, these operator classes will not outperform the equivalent
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standard B-tree index methods, and they lack one major feature of the
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standard B-tree code: the ability to enforce uniqueness. However,
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they are useful for GIN testing and as a base for developing other
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GIN operator classes. Also, for queries that test both a GIN-indexable
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column and a B-tree-indexable column, it might be more efficient to create
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a multicolumn GIN index that uses one of these operator classes than to create
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two separate indexes that would have to be combined via bitmap ANDing.
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</para>
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<sect2>
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<title>Example Usage</title>
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<programlisting>
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CREATE TABLE test (a int4);
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-- create index
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CREATE INDEX testidx ON test USING GIN (a);
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-- query
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SELECT * FROM test WHERE a < 10;
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</programlisting>
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</sect2>
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<sect2>
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<title>Authors</title>
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<para>
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Teodor Sigaev (<email>teodor@stack.net</email>) and
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Oleg Bartunov (<email>oleg@sai.msu.su</email>). See
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<ulink url="http://www.sai.msu.su/~megera/oddmuse/index.cgi/Gin"></ulink>
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for additional information.
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</para>
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</sect2>
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</sect1>
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