bit.out

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

-- bit check
CREATE TABLE bittmp (a bit(33));
\copy bittmp from 'data/bit.data'
SET enable_seqscan=on;
SELECT count(*) FROM bittmp WHERE a <   '011011000100010111011000110000100';
 count 
-------
   249
(1 row)

SELECT count(*) FROM bittmp WHERE a <=  '011011000100010111011000110000100';
 count 
-------
   250
(1 row)

SELECT count(*) FROM bittmp WHERE a  =  '011011000100010111011000110000100';
 count 
-------
     1
(1 row)

SELECT count(*) FROM bittmp WHERE a >=  '011011000100010111011000110000100';
 count 
-------
   351
(1 row)

SELECT count(*) FROM bittmp WHERE a >   '011011000100010111011000110000100';
 count 
-------
   350
(1 row)

CREATE INDEX bitidx ON bittmp USING GIST ( a );
SET enable_seqscan=off;
SELECT count(*) FROM bittmp WHERE a <   '011011000100010111011000110000100';
 count 
-------
   249
(1 row)

SELECT count(*) FROM bittmp WHERE a <=  '011011000100010111011000110000100';
 count 
-------
   250
(1 row)

SELECT count(*) FROM bittmp WHERE a  =  '011011000100010111011000110000100';
 count 
-------
     1
(1 row)

SELECT count(*) FROM bittmp WHERE a >=  '011011000100010111011000110000100';
 count 
-------
   351
(1 row)

SELECT count(*) FROM bittmp WHERE a >   '011011000100010111011000110000100';
 count 
-------
   350
(1 row)