CREATE TABLE t1 (f1 INT NOT NULL, f2 INT NOT NULL,
UNIQUE KEY uidx2(f1,f2),
UNIQUE KEY uidx1(f2)) ENGINE=InnoDB;
INSERT INTO t1 VALUES(1 , 1 );
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` int(11 ) NOT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `uidx2` (`f1`,`f2`),
UNIQUE KEY `uidx1` (`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
SET DEBUG_SYNC = 'innodb_inplace_alter_table_enter
SIGNAL conc_dml WAIT_FOR go_ahead';
ALTER TABLE t1 CHANGE COLUMN f1 f11 INT, ALGORITHM=INPLACE;
connect con1,localhost,root,,;
SET DEBUG_SYNC = 'now WAIT_FOR conc_dml' ;
DELETE FROM t1;
SET DEBUG_SYNC = 'now SIGNAL go_ahead' ;
connection default;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f11` int(11 ) DEFAULT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `uidx1` (`f2`),
UNIQUE KEY `uidx2` (`f11`,`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
DROP TABLE t1;
CREATE TABLE t1(f1 INT, f2 INT,
PRIMARY KEY(f1, f2),
UNIQUE INDEX uidx2 (f1, f2),
UNIQUE INDEX uidx1 (f2))ENGINE=InnoDB;
INSERT INTO t1 VALUES(2 , 2 );
ALTER TABLE t1 DROP PRIMARY KEY;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` int(11 ) NOT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `uidx2` (`f1`,`f2`),
UNIQUE KEY `uidx1` (`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
SET DEBUG_SYNC = 'innodb_inplace_alter_table_enter
SIGNAL conc_dml WAIT_FOR go_ahead';
ALTER TABLE t1 CHANGE COLUMN f1 f11 INT, ALGORITHM=INPLACE;
connection con1;
SET DEBUG_SYNC = 'now WAIT_FOR conc_dml' ;
INSERT INTO t1 VALUES(1 , 1 ), (1 , 1 );
ERROR 23000 : Duplicate entry '1-1' for key 'uidx2'
SET DEBUG_SYNC = 'now SIGNAL go_ahead' ;
connection default;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f11` int(11 ) DEFAULT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `uidx1` (`f2`),
UNIQUE KEY `uidx2` (`f11`,`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
CHECK TABLE t1;
Table Op Msg_type Msg_text
test.t1 check status OK
DROP TABLE t1;
SET SQL_MODE= strict_trans_tables;
CREATE TABLE t1(a INT UNIQUE) ENGINE=InnoDB;
INSERT INTO t1 VALUES(1 );
SET DEBUG_SYNC='row_log_table_apply1_before SIGNAL dml WAIT_FOR dml_done' ;
ALTER TABLE t1 MODIFY COLUMN a INT NOT NULL;
connection con1;
SET DEBUG_SYNC='now WAIT_FOR dml' ;
BEGIN;
INSERT INTO t1 SET a=NULL;
COMMIT;
set DEBUG_SYNC='now SIGNAL dml_done' ;
connection default;
ERROR 22004 : Invalid use of NULL value
DROP TABLE t1;
disconnect con1;
SET DEBUG_SYNC="RESET" ;
SET SQL_MODE=DEFAULT;
CREATE TABLE t1(f1 INT NOT NULL, f2 INT NOT NULL, PRIMARY KEY(f1, f2),
UNIQUE KEY(f2))ENGINE=InnoDB;
ALTER TABLE t1 DROP PRIMARY KEY;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` int(11 ) NOT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `f2` (`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
DROP TABLE t1;
CREATE TABLE t1(f1 INT NOT NULL, f2 INT NOT NULL,
UNIQUE KEY(f2), UNIQUE KEY(f2))ENGINE=InnoDB;
Warnings:
Note 1831 Duplicate index `f2_2`. This is deprecated and will be disallowed in a future release
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` int(11 ) NOT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `f2` (`f2`),
UNIQUE KEY `f2_2` (`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
ALTER TABLE t1 DROP INDEX f2, ALGORITHM=INPLACE;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` int(11 ) NOT NULL,
`f2` int(11 ) NOT NULL,
UNIQUE KEY `f2_2` (`f2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
DROP TABLE t1;
Messung V0.5 in Prozent C=56 H=100 G=80
¤ Dauer der Verarbeitung: 0.8 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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