Coinstraints in DELETE statement should be evaluated per whole query (instead of per isolated row)

CREATE TABLE t (

  id int NOT NULL,

  parent_id int,

  name varchar(64) NOT NULL,

  PRIMARY KEY (id),

  UNIQUE KEY (id),

  CONSTRAINT fk_parent FOREIGN KEY (parent_id) REFERENCES t(id)

);

insert into t values

  (1, null, 'A'),

  (2, 1, 'B'),

  (3, 1, 'B'),

  (4, 4, 'C');

/* id=3 can be deleted and then id=1 */

delete from t where id = 3 or id = 1;

// Cannot delete or update a parent row: a foreign key constraint fails

// (`fiddle`.`t`, CONSTRAINT `fk_parent` FOREIGN KEY (`parent_id`) REFERENCES `t` (`id`))

/* id=4 can be deleted as it is cyclic to itself */

delete from t where id = 4;

// Cannot delete or update a parent row: a foreign key constraint fails

// (`fiddle`.`t`, CONSTRAINT `fk_parent` FOREIGN KEY (`parent_id`) REFERENCES `t` (`id`))