mirror of
https://github.com/MariaDB/server.git
synced 2025-10-30 18:36:12 +01:00
44 lines
1.6 KiB
Text
44 lines
1.6 KiB
Text
CREATE TABLE t1 (D INT) ENGINE=innodb;
|
|
INSERT INTO t1 VALUES (10);
|
|
ALTER TABLE t1 MODIFY COLUMN d INT;
|
|
ALTER TABLE t1 ADD INDEX my_d (d);
|
|
SHOW CREATE TABLE t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`d` int(11) DEFAULT NULL,
|
|
KEY `my_d` (`d`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9);
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
INSERT INTO t1 SELECT * FROM t1;
|
|
EXPLAIN SELECT d FROM t1 WHERE d = 5;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref my_d my_d 5 const 128 Using index
|
|
EXPLAIN SELECT D FROM t1 WHERE D = 5;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref my_d my_d 5 const 128 Using index
|
|
ALTER TABLE t1 DROP INDEX my_d;
|
|
ALTER TABLE t1 MODIFY COLUMN D INT;
|
|
ANALYZE TABLE t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 analyze status Engine-independent statistics collected
|
|
test.t1 analyze status OK
|
|
ALTER TABLE t1 ADD INDEX my_d (D);
|
|
EXPLAIN SELECT d FROM t1 WHERE d = 5;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref my_d my_d 5 const 128 Using index
|
|
EXPLAIN SELECT D FROM t1 WHERE D = 5;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref my_d my_d 5 const 128 Using index
|
|
SHOW CREATE TABLE t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`D` int(11) DEFAULT NULL,
|
|
KEY `my_d` (`D`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
|
|
DROP TABLE t1;
|