MariaDB 10.6

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CREATE TABLE IF NOT EXISTS user (
id INT NOT NULL AUTO_INCREMENT,
name VARCHAR(55),
PRIMARY KEY (`id`)
);

CREATE TABLE IF NOT EXISTS user_map (
map_id INT NOT NULL AUTO_INCREMENT,
user_a INT,
user_b INT,
  PRIMARY KEY (`map_id`),
  UNIQUE KEY `one_way` (`user_a`,`user_b`),
  UNIQUE KEY `other_way` (`user_b`,`user_a`),
  CONSTRAINT `acc_connections_ibfk_1` FOREIGN KEY (`user_a`) REFERENCES `user` (`id`) ON UPDATE CASCADE ON DELETE CASCADE,
  CONSTRAINT `acc_connections_ibfk_2` FOREIGN KEY (`user_b`) REFERENCES `user` (`id`) ON UPDATE CASCADE ON DELETE CASCADE
);
INSERT INTO user (name) VALUES ("User A");
INSERT INTO user_map (user_a,user_b) VALUES (1,1);
UPDATE user set id = 10 where id = 1;
Cannot add or update a child row: a foreign key constraint fails (`db_682912558`.`user_map`, CONSTRAINT `acc_connections_ibfk_2` FOREIGN KEY (`user_b`) REFERENCES `user` (`id`) ON DELETE CASCADE ON UPDATE CASCADE)