83 lines
1.6 KiB
Plaintext
83 lines
1.6 KiB
Plaintext
|
-- 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)
|
||
|
|
|