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c16c3b9e47
- Add a Sort_priority_queue_sorts status variable.
1200 lines
26 KiB
Text
1200 lines
26 KiB
Text
#
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# Bug #30584: delete with order by and limit clauses does not use
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# limit efficiently
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#
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CREATE TABLE t1 (i INT);
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INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
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(20),(21),(22),(23),(24),(25);
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CREATE TABLE t2(a INT, i INT PRIMARY KEY);
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INSERT INTO t2 (i) SELECT i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
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a i
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NULL 11
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NULL 12
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NULL 13
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NULL 14
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NULL 15
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 4
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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FLUSH STATUS;
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DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 4
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i;
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a i
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NULL 16
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NULL 17
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NULL 18
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DROP TABLE t2;
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#
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# index on field prefix:
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#
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CREATE TABLE t2(a INT, i CHAR(2), INDEX(i(1)));
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INSERT INTO t2 (i) SELECT i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
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a i
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NULL 11
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NULL 12
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NULL 13
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NULL 14
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NULL 15
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 1
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Sort_range 0
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Sort_rows 5
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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FLUSH STATUS;
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DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 8
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 5
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i;
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a i
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NULL 16
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NULL 17
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NULL 18
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DROP TABLE t2;
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#
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# constant inside ORDER BY list, should use filesort
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# on a small table
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#
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CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
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INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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a b c d
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10 10 10 NULL
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 1
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Sort_range 0
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Sort_rows 1
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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FLUSH STATUS;
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DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 1
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 1
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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## should be 5 (previous LIMIT)
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SELECT 1 - COUNT(*) FROM t2 WHERE b = 10;
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1 - COUNT(*)
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1
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DROP TABLE t2;
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#
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# same test as above (constant inside ORDER BY list), but with
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# a larger table - should not use filesort
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#
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CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
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INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
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INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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a b c d
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10 10 10 NULL
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10 10 10 NULL
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10 10 10 NULL
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10 10 10 NULL
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10 10 10 NULL
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 1
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 4
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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FLUSH STATUS;
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DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 1
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 4
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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## should be 5 (previous LIMIT)
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SELECT 257 - COUNT(*) FROM t2 WHERE b = 10;
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257 - COUNT(*)
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5
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DROP TABLE t2;
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#
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# as above + partial index, should use filesort
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#
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CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b(1),c));
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INSERT INTO t2 SELECT i, i, i, i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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a b c d
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10 10 10 10
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 1
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Sort_range 0
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Sort_rows 1
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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FLUSH STATUS;
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DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 1
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 1
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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SELECT * FROM t2 WHERE b = 10 ORDER BY a, c;
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a b c d
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DROP TABLE t2;
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#
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# as above but index is without HA_READ_ORDER flag, should use filesort
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#
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CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b,c)) ENGINE=HEAP;
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INSERT INTO t2 SELECT i, i, i, i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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a b c d
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10 10 10 10
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 1
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Sort_range 0
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Sort_rows 1
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 1
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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FLUSH STATUS;
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DELETE FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 1
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 1
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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SELECT * FROM t2 WHERE b = 10 ORDER BY a, c;
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a b c d
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DROP TABLE t2;
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#
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# quick select is Index Merge, should use filesort
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#
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CREATE TABLE t2 (i INT, key1 INT, key2 INT, INDEX (key1), INDEX (key2));
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INSERT INTO t2 (key1, key2) SELECT i, i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
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i key1 key2
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NULL 10 10
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NULL 11 11
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NULL 12 12
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NULL 13 13
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 1
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Sort_rows 4
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 2
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Handler_read_last 0
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Handler_read_next 7
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Handler_read_prev 0
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Handler_read_rnd 4
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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EXPLAIN EXTENDED SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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x x x x x x x x x x Using sort_union(key1,key2); Using where; Using filesort
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Warnings:
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x x x
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FLUSH STATUS;
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DELETE FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 1
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Sort_rows 4
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 2
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Handler_read_last 0
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Handler_read_next 7
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Handler_read_prev 0
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Handler_read_rnd 8
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
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i key1 key2
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EXPLAIN EXTENDED SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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x x x x x x x x x x Using sort_union(key1,key2); Using where; Using filesort
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Warnings:
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x x x
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DROP TABLE t2;
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#
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# reverse quick select, should not use filesort
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#
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CREATE TABLE t2(a INT, i INT PRIMARY KEY);
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INSERT INTO t2 (i) SELECT i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
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a i
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NULL 18
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NULL 17
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NULL 16
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NULL 15
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NULL 14
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 4
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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FLUSH STATUS;
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DELETE FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 4
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i;
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a i
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NULL 11
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NULL 12
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NULL 13
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DROP TABLE t2;
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#
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# mixed sorting direction, should use filesort
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#
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CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
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INSERT INTO t2 SELECT i, i, i FROM t1;
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FLUSH STATUS;
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SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5;
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a b c
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10 10 10
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11 11 11
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12 12 12
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13 13 13
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14 14 14
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 1
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Sort_range 0
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Sort_rows 5
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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FLUSH STATUS;
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DELETE FROM t2 ORDER BY a, b DESC LIMIT 5;
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 16
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Sort_scan 1
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_rnd 5
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 17
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SELECT * FROM t2 ORDER BY a, b DESC;
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a b c
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15 15 15
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16 16 16
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17 17 17
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18 18 18
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19 19 19
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20 20 20
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21 21 21
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22 22 22
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23 23 23
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24 24 24
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25 25 25
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DROP TABLE t2;
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#
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# LIMIT with no WHERE and DESC direction, should not use filesort
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#
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CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
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INSERT INTO t2 (a, b) SELECT i, i FROM t1;
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INSERT INTO t2 (a, b) SELECT t1.i, t1.i FROM t1, t1 x1, t1 x2;
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FLUSH STATUS;
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SELECT * FROM t2 ORDER BY a, b LIMIT 5;
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a b c
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10 10 NULL
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10 10 NULL
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10 10 NULL
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10 10 NULL
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10 10 NULL
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SHOW SESSION STATUS LIKE 'Sort%';
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Variable_name Value
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Sort_merge_passes 0
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Sort_priority_queue_sorts 0
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Sort_range 0
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Sort_rows 0
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Sort_scan 0
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SHOW STATUS LIKE 'Handler_read_%';
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Variable_name Value
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Handler_read_first 1
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Handler_read_key 0
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Handler_read_last 0
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Handler_read_next 4
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Handler_read_prev 0
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Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
|
|
a b c
|
|
25 25 NULL
|
|
25 25 NULL
|
|
25 25 NULL
|
|
25 25 NULL
|
|
25 25 NULL
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 1
|
|
Handler_read_next 0
|
|
Handler_read_prev 4
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
DELETE FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 1
|
|
Handler_read_next 0
|
|
Handler_read_prev 4
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
SELECT * FROM t2 WHERE c = 10 ORDER BY a DESC, b DESC;
|
|
a b c
|
|
DROP TABLE t1, t2;
|
|
#
|
|
# Bug #36569: UPDATE ... WHERE ... ORDER BY... always does a filesort
|
|
# even if not required
|
|
#
|
|
CREATE TABLE t1 (i INT);
|
|
INSERT INTO t1 VALUES (10),(11),(12),(13),(14),(15),(16),(17),(18),(19),
|
|
(20),(21),(22),(23),(24),(25);
|
|
CREATE TABLE t2(a INT, i INT PRIMARY KEY);
|
|
INSERT INTO t2 (i) SELECT i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
|
|
a i
|
|
NULL 11
|
|
NULL 12
|
|
NULL 13
|
|
NULL 14
|
|
NULL 15
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 1
|
|
Handler_read_last 0
|
|
Handler_read_next 4
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 1
|
|
Handler_read_last 0
|
|
Handler_read_next 4
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 5
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i;
|
|
a i
|
|
10 11
|
|
10 12
|
|
10 13
|
|
10 14
|
|
10 15
|
|
NULL 16
|
|
NULL 17
|
|
NULL 18
|
|
DROP TABLE t2;
|
|
#
|
|
# index on field prefix:
|
|
#
|
|
CREATE TABLE t2(a INT, i CHAR(2), INDEX(i(1)));
|
|
INSERT INTO t2 (i) SELECT i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
|
|
a i
|
|
NULL 11
|
|
NULL 12
|
|
NULL 13
|
|
NULL 14
|
|
NULL 15
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 5
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 5
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 5
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i;
|
|
a i
|
|
10 11
|
|
10 12
|
|
10 13
|
|
10 14
|
|
10 15
|
|
NULL 16
|
|
NULL 17
|
|
NULL 18
|
|
DROP TABLE t2;
|
|
#
|
|
# constant inside ORDER BY list, should use filesort
|
|
# on a small table
|
|
#
|
|
CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
|
|
INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
a b c d
|
|
10 10 10 NULL
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 1
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 1
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 1
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
## should be 5 (previous LIMIT)
|
|
SELECT COUNT(*) FROM t2 WHERE b = 10 AND d = 10 ORDER BY a, c;
|
|
COUNT(*)
|
|
1
|
|
DROP TABLE t2;
|
|
#
|
|
# same test as above (constant inside ORDER BY list), but with
|
|
# a larger table - should not use filesort
|
|
#
|
|
CREATE TABLE t2(a INT, b INT, c INT, d INT, INDEX(a, b, c));
|
|
INSERT INTO t2 (a, b, c) SELECT i, i, i FROM t1;
|
|
INSERT INTO t2 (a, b, c) SELECT t1.i, t1.i, t1.i FROM t1, t1 x1, t1 x2;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
a b c d
|
|
10 10 10 NULL
|
|
10 10 10 NULL
|
|
10 10 10 NULL
|
|
10 10 10 NULL
|
|
10 10 10 NULL
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 1
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 4
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 1
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 4
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 5
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
## should be 5 (previous LIMIT)
|
|
SELECT COUNT(*) FROM t2 WHERE b = 10 AND d = 10 ORDER BY a, c;
|
|
COUNT(*)
|
|
5
|
|
DROP TABLE t2;
|
|
#
|
|
# as above + partial index, should use filesort
|
|
#
|
|
CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b(1),c));
|
|
INSERT INTO t2 SELECT i, i, i, i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
a b c d
|
|
10 10 10 10
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 1
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 1
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 1
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
SELECT * FROM t2 WHERE b = 10 ORDER BY a, c;
|
|
a b c d
|
|
10 10 10 10
|
|
DROP TABLE t2;
|
|
#
|
|
# as above but index is without HA_READ_ORDER flag, should use filesort
|
|
#
|
|
CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), d CHAR(2), INDEX (a,b,c)) ENGINE=HEAP;
|
|
INSERT INTO t2 SELECT i, i, i, i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
a b c d
|
|
10 10 10 10
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 1
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 1
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET d = 10 WHERE b = 10 ORDER BY a, c LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 1
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 1
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
SELECT * FROM t2 WHERE b = 10 ORDER BY a, c;
|
|
a b c d
|
|
10 10 10 10
|
|
DROP TABLE t2;
|
|
#
|
|
# quick select is Index Merge, should use filesort
|
|
#
|
|
CREATE TABLE t2 (i INT, key1 INT, key2 INT, INDEX (key1), INDEX (key2));
|
|
INSERT INTO t2 (key1, key2) SELECT i, i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
|
|
i key1 key2
|
|
NULL 10 10
|
|
NULL 11 11
|
|
NULL 12 12
|
|
NULL 13 13
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 1
|
|
Sort_rows 4
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 2
|
|
Handler_read_last 0
|
|
Handler_read_next 7
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 4
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
EXPLAIN EXTENDED SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
|
|
id select_type table type possible_keys key key_len ref rows filtered Extra
|
|
x x x x x x x x x x Using sort_union(key1,key2); Using where; Using filesort
|
|
Warnings:
|
|
x x x
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET i = 123 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 1
|
|
Sort_rows 4
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 2
|
|
Handler_read_last 0
|
|
Handler_read_next 7
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 8
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
|
|
i key1 key2
|
|
123 10 10
|
|
123 11 11
|
|
123 12 12
|
|
123 13 13
|
|
EXPLAIN EXTENDED SELECT * FROM t2 WHERE key1 < 13 or key2 < 14 ORDER BY key1;
|
|
id select_type table type possible_keys key key_len ref rows filtered Extra
|
|
x x x x x x x x x x Using sort_union(key1,key2); Using where; Using filesort
|
|
Warnings:
|
|
x x x
|
|
DROP TABLE t2;
|
|
#
|
|
# reverse quick select, should not use filesort
|
|
#
|
|
CREATE TABLE t2(a INT, i INT PRIMARY KEY);
|
|
INSERT INTO t2 (i) SELECT i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
|
|
a i
|
|
NULL 18
|
|
NULL 17
|
|
NULL 16
|
|
NULL 15
|
|
NULL 14
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 1
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 4
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET a = 10 WHERE i > 10 AND i <= 18 ORDER BY i DESC LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 1
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 4
|
|
Handler_read_rnd 5
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
SELECT * FROM t2 WHERE i > 10 AND i <= 18 ORDER BY i;
|
|
a i
|
|
NULL 11
|
|
NULL 12
|
|
NULL 13
|
|
10 14
|
|
10 15
|
|
10 16
|
|
10 17
|
|
10 18
|
|
DROP TABLE t2;
|
|
#
|
|
# mixed sorting direction, should use filesort
|
|
#
|
|
CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
|
|
INSERT INTO t2 SELECT i, i, i FROM t1;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 ORDER BY a, b DESC LIMIT 5;
|
|
a b c
|
|
10 10 10
|
|
11 11 11
|
|
12 12 12
|
|
13 13 13
|
|
14 14 14
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 5
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET c = 10 ORDER BY a, b DESC LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 1
|
|
Sort_range 0
|
|
Sort_rows 5
|
|
Sort_scan 1
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 5
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 17
|
|
SELECT * FROM t2 WHERE c = 10 ORDER BY a, b DESC;
|
|
a b c
|
|
10 10 10
|
|
11 11 10
|
|
12 12 10
|
|
13 13 10
|
|
14 14 10
|
|
DROP TABLE t2;
|
|
#
|
|
# LIMIT with no WHERE and DESC direction, should not use filesort
|
|
#
|
|
CREATE TABLE t2 (a CHAR(2), b CHAR(2), c CHAR(2), INDEX (a, b));
|
|
INSERT INTO t2 (a, b) SELECT i, i FROM t1;
|
|
INSERT INTO t2 (a, b) SELECT t1.i, t1.i FROM t1, t1 x1, t1 x2;
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 ORDER BY a, b LIMIT 5;
|
|
a b c
|
|
10 10 NULL
|
|
10 10 NULL
|
|
10 10 NULL
|
|
10 10 NULL
|
|
10 10 NULL
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 1
|
|
Handler_read_key 0
|
|
Handler_read_last 0
|
|
Handler_read_next 4
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
SELECT * FROM t2 ORDER BY a DESC, b DESC LIMIT 5;
|
|
a b c
|
|
25 25 NULL
|
|
25 25 NULL
|
|
25 25 NULL
|
|
25 25 NULL
|
|
25 25 NULL
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 1
|
|
Handler_read_next 0
|
|
Handler_read_prev 4
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
FLUSH STATUS;
|
|
UPDATE t2 SET c = 10 ORDER BY a DESC, b DESC LIMIT 5;
|
|
SHOW SESSION STATUS LIKE 'Sort%';
|
|
Variable_name Value
|
|
Sort_merge_passes 0
|
|
Sort_priority_queue_sorts 0
|
|
Sort_range 0
|
|
Sort_rows 0
|
|
Sort_scan 0
|
|
SHOW STATUS LIKE 'Handler_read_%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 0
|
|
Handler_read_last 1
|
|
Handler_read_next 0
|
|
Handler_read_prev 4
|
|
Handler_read_rnd 5
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 0
|
|
SELECT * FROM t2 WHERE c = 10 ORDER BY a DESC, b DESC;
|
|
a b c
|
|
25 25 10
|
|
25 25 10
|
|
25 25 10
|
|
25 25 10
|
|
25 25 10
|
|
DROP TABLE t1, t2;
|
|
#
|
|
# Bug #53742: UPDATEs have no effect after applying patch for bug 36569
|
|
#
|
|
CREATE TABLE t1 (
|
|
pk INT NOT NULL AUTO_INCREMENT,
|
|
c1_idx CHAR(1) DEFAULT 'y',
|
|
c2 INT,
|
|
PRIMARY KEY (pk),
|
|
INDEX c1_idx (c1_idx)
|
|
) ENGINE=InnoDB;
|
|
INSERT INTO t1 VALUES (), (), (), ();
|
|
SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
|
|
pk c1_idx c2
|
|
4 y NULL
|
|
3 y NULL
|
|
UPDATE t1 SET c2 = 0 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
|
|
SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
|
|
pk c1_idx c2
|
|
4 y 0
|
|
3 y 0
|
|
SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC;
|
|
pk c1_idx c2
|
|
4 y 0
|
|
3 y 0
|
|
2 y NULL
|
|
1 y NULL
|
|
DELETE FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC LIMIT 2;
|
|
SELECT * FROM t1 WHERE c1_idx = 'y' ORDER BY pk DESC;
|
|
pk c1_idx c2
|
|
2 y NULL
|
|
1 y NULL
|
|
DROP TABLE t1;
|