This is a B-Tree implementation using GiST that supports the int2, int4,int8, float4, float8 timestamp with/without time zone, timewith/without time zone, date, interval, oid, money, macaddr, char,varchar/text, bytea, numeric, bit, varbit and inet/cidr types.All work was done by Teodor Sigaev (teodor@stack.net) , Oleg Bartunov(oleg@sai.msu.su), Janko Richter (jankorichter@yahoo.de).See http://www.sai.msu.su/~megera/postgres/gist for additionalinformation.NEWS:     Apr 17, 2004 - Performance optimizing     Jan 21, 2004 - add support for bytea, numeric, bit, varbit, inet/cidr     Jan 17, 2004 - Reorganizing code and add support for char, varchar/text     Jan 10, 2004 - btree_gist now support oid , timestamp with time zone ,                    time with and without time zone, date , interval                    money, macaddr     Feb  5, 2003 - btree_gist now support int2, int8, float4, float8     NOTICE:     This version will only work with PostgreSQL version 7.4 and above     because of changes in the system catalogs and the function call     interface.          If you want to index varchar attributes, you have to index using     the function text(<varchar>):     Example:       CREATE TABLE test ( a varchar(23) );       CREATE INDEX testidx ON test USING GIST ( text(a) );INSTALLATION:  gmake  gmake install  -- load functions  psql <database> < btree_gist.sqlREGRESSION TEST:   gmake installcheckEXAMPLE USAGE:   create table test (a int4);   -- create index   create index testidx on test using gist (a);   -- query   select * from test where a < 10;