btree\_gin {#btree-gin}
==========

btree\_gin

`btree_gin` provides sample GIN operator classes that implement B-tree
equivalent behavior for the data types `int2`, `int4`, `int8`, `float4`,
`float8`, `timestamp with time zone`, `timestamp without time zone`,
`time with time zone`, `time without time zone`, `date`, `interval`,
`oid`, `money`, `"char"`, `varchar`, `text`, `bytea`, `bit`, `varbit`,
`macaddr`, `macaddr8`, `inet`, `cidr`, `uuid`, `name`, `bool`, `bpchar`,
and all `enum` types.

In general, these operator classes will not outperform the equivalent
standard B-tree index methods, and they lack one major feature of the
standard B-tree code: the ability to enforce uniqueness. However, they
are useful for GIN testing and as a base for developing other GIN
operator classes. Also, for queries that test both a GIN-indexable
column and a B-tree-indexable column, it might be more efficient to
create a multicolumn GIN index that uses one of these operator classes
than to create two separate indexes that would have to be combined via
bitmap ANDing.

This module is considered "trusted", that is, it can be installed by
non-superusers who have `CREATE` privilege on the current database.

Example Usage
-------------

    CREATE TABLE test (a int4);
    -- create index
    CREATE INDEX testidx ON test USING GIN (a);
    -- query
    SELECT * FROM test WHERE a < 10;

Authors
-------

Teodor Sigaev (<teodor@stack.net>) and Oleg Bartunov
(<oleg@sai.msu.su>). See
[](http://www.sai.msu.su/~megera/oddmuse/index.cgi/Gin) for additional
information.
