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 , inet , and cidr .

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.

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