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