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#
# MDEV-22230 : Unexpected ER_ERROR_ON_RENAME upon DROP
# non-existing FOREIGN KEY
#
CREATE TABLE t1 (a INT) ENGINE=InnoDB;
ALTER TABLE t1 DROP FOREIGN KEY x, ALGORITHM=COPY;
ERROR 42000: Can't DROP FOREIGN KEY `x`; check that it exists
ALTER TABLE t1 DROP FOREIGN KEY x, ALGORITHM=INPLACE;
ERROR 42000: Can't DROP FOREIGN KEY `x`; check that it exists
DROP TABLE t1;
CREATE TABLE t1 (a INT, KEY(a)) ENGINE=InnoDB;
CREATE TABLE t2 (a INT, FOREIGN KEY fk_id (a) REFERENCES t1(a))ENGINE=InnoDB;
CREATE TABLE t3 (a INT, FOREIGN KEY fk_1 (a) REFERENCES t1(a))ENGINE=InnoDB;
ALTER TABLE t3 DROP FOREIGN KEY IF EXISTS fk_id;
Warnings:
Note 1091 Can't DROP FOREIGN KEY `fk_id`; check that it exists
DROP TABLE t3, t2;
ALTER TABLE t1 MODIFY COLUMN a VARCHAR(2), DROP FOREIGN KEY IF EXISTS x;
Warnings:
Note 1091 Can't DROP FOREIGN KEY `x`; check that it exists
DROP TABLE t1;
CREATE DATABASE best;
CREATE TABLE best.t1(f1 INT, KEY(f1))ENGINE=InnoDB;
CREATE TABLE best.t2(f1 INT, FOREIGN KEY foo(f1) REFERENCES t1(f1))ENGINE=InnoDB;
CREATE TABLE t1(f1 INT, KEY(f1))ENGINE=InnoDB;
CREATE TABLE t2(f1 INT, FOREIGN KEY foo(f1) REFERENCES t1(f1))ENGINE=InnoDB;
ALTER TABLE t2 DROP FOREIGN KEY foo;
ALTER TABLE t2 DROP FOREIGN KEY foo;
ERROR 42000: Can't DROP FOREIGN KEY `foo`; check that it exists
ALTER TABLE t2 DROP FOREIGN KEY IF EXISTS foo;
Warnings:
Note 1091 Can't DROP FOREIGN KEY `foo`; check that it exists
SHOW CREATE TABLE best.t2;
Table Create Table
t2 CREATE TABLE `t2` (
`f1` int(11) DEFAULT NULL,
KEY `foo` (`f1`),
CONSTRAINT `foo` FOREIGN KEY (`f1`) REFERENCES `t1` (`f1`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN;
ID FOR_NAME REF_NAME N_COLS TYPE
best/foo best/t2 best/t1 1 0
DROP TABLE best.t2, best.t1, t2, t1;
DROP DATABASE best;
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