call mtr.add_suppression("InnoDB: In ALTER TABLE .* has or is referenced in foreign key constraints which are not compatible with the new table definition.");
# modify child column NOT NULL on UPDATE CASCADE..parent column NULL
CREATE TABLE t1(f1 INT, f2 INT, PRIMARY KEY(f1), KEY(f2))ENGINE=InnoDB;
CREATE TABLE t2(f1 INT, FOREIGN KEY(f1) REFERENCES t1(f2) ON UPDATE CASCADE)ENGINE=InnoDB;
ALTER TABLE t2 MODIFY COLUMN f1 INT NOT NULL;
ERROR HY000: Column 'f1' cannot be NOT NULL: needed in a foreign key constraint '1' SET NULL
INSERT INTO t1 VALUES(1, 1);
INSERT INTO t2 VALUES(1);
UPDATE t1 SET f2= NULL;
DELETE FROM t2;
SELECT * FROM t1;
f1	f2
1	NULL
UPDATE t1 SET f2 = NULL;
SELECT * FROM t1;
f1	f2
1	NULL
DROP TABLE t2, t1;
# modify child column NOT NULL ON UPDATE SET NULL
CREATE TABLE t1(f1 INT, f2 INT, PRIMARY KEY(f1), KEY(f2))ENGINE=InnoDB;
CREATE TABLE t2(f1 INT, f2 INT, FOREIGN KEY(f1) REFERENCES t1(f1) ON UPDATE SET NULL)ENGINE=InnoDB;
ALTER TABLE t2 MODIFY COLUMN f1 INT NOT NULL;
ERROR HY000: Column 'f1' cannot be NOT NULL: needed in a foreign key constraint '1' SET NULL
INSERT INTO t1 VALUES(1, 1);
INSERT INTO t2 VALUES(1, 1);
UPDATE t1 SET f1= 2;
SELECT * FROM t2;
f1	f2
NULL	1
DROP TABLE t2, t1;
# modify child column NOT NULL ON DELETE SET NULL
CREATE TABLE t1(f1 INT, f2 INT, PRIMARY KEY(f1), KEY(f2))ENGINE=InnoDB;
CREATE TABLE t2(f1 INT, f2 INT, FOREIGN KEY (f2) REFERENCES t1(f2) ON DELETE SET NULL)ENGINE=InnoDB;
ALTER TABLE t2 MODIFY COLUMN f2 INT NOT NULL;
ERROR HY000: Column 'f2' cannot be NOT NULL: needed in a foreign key constraint '1' SET NULL
DROP TABLE t2, t1;
# modify parent column NULL ON UPDATE CASCADE child column NOT NULL
CREATE TABLE `t#1`(f1 INT, f2 INT NOT NULL, PRIMARY KEY(f1), KEY(f2))ENGINE=InnoDB;
CREATE TABLE `t#2`(f1 INT NOT NULL,
FOREIGN KEY(f1) REFERENCES `t#1`(f2)
ON UPDATE CASCADE)ENGINE=InnoDB;
ALTER TABLE `t#1` MODIFY COLUMN f2 INT;
ERROR HY000: Cannot change column 'f2': used in a foreign key constraint '1' of table 'test.t#2'
INSERT INTO `t#1` VALUES(1, 1);
INSERT INTO `t#2` VALUES(1);
UPDATE `t#1` SET f2= NULL;
ERROR 23000: Column 'f2' cannot be null
DELETE FROM `t#2`;
SELECT * FROM `t#1`;
f1	f2
1	1
DROP TABLE `t#2`, `t#1`;
CREATE TABLE t1(f1 INT NOT NULL AUTO_INCREMENT,
f2 INT DEFAULT NULL,
PRIMARY KEY(f1),
FOREIGN KEY(f2) REFERENCES t1(f1))ENGINE=InnoDB;
CREATE TABLE t2 (f1 INT NOT NULL,
f2 INT NOT NULL,
f3 INT DEFAULT NULL,
PRIMARY KEY(f1, f2),
FOREIGN KEY(f2, f3) REFERENCES t1(f2, f1)
ON UPDATE CASCADE)ENGINE=InnoDB;
ERROR HY000: Can't create table `test`.`t2` (errno: 150 "Foreign key constraint is incorrectly formed")
DROP TABLE IF EXISTS t2;
DROP TABLE IF EXISTS t1;