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|
-- char check
CREATE TABLE chartmp (a char(32));
\copy chartmp from 'data/char.data'
SET enable_seqscan=on;
SELECT count(*) FROM chartmp WHERE a < '31b0'::char(32);
count
-------
587
(1 row)
SELECT count(*) FROM chartmp WHERE a <= '31b0'::char(32);
count
-------
588
(1 row)
SELECT count(*) FROM chartmp WHERE a = '31b0'::char(32);
count
-------
1
(1 row)
SELECT count(*) FROM chartmp WHERE a >= '31b0'::char(32);
count
-------
401
(1 row)
SELECT count(*) FROM chartmp WHERE a > '31b0'::char(32);
count
-------
400
(1 row)
CREATE INDEX charidx ON chartmp USING GIST ( a );
SET enable_seqscan=off;
SELECT count(*) FROM chartmp WHERE a < '31b0'::char(32);
count
-------
587
(1 row)
SELECT count(*) FROM chartmp WHERE a <= '31b0'::char(32);
count
-------
588
(1 row)
SELECT count(*) FROM chartmp WHERE a = '31b0'::char(32);
count
-------
1
(1 row)
SELECT count(*) FROM chartmp WHERE a >= '31b0'::char(32);
count
-------
401
(1 row)
SELECT count(*) FROM chartmp WHERE a > '31b0'::char(32);
count
-------
400
(1 row)
-- Test index-only scans
SET enable_bitmapscan=off;
EXPLAIN (COSTS OFF)
SELECT * FROM chartmp WHERE a BETWEEN '31a' AND '31c';
QUERY PLAN
---------------------------------------------------------------
Index Only Scan using charidx on chartmp
Index Cond: ((a >= '31a'::bpchar) AND (a <= '31c'::bpchar))
(2 rows)
SELECT * FROM chartmp WHERE a BETWEEN '31a' AND '31c';
a
----------------------------------
31b0
(1 row)
|
