MySQL 5.7

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CREATE TABLE parent (
    id INT NOT NULL,
    PRIMARY KEY (id)
) ENGINE=INNODB;
-- только InnoDB
CREATE TABLE child (
    id INT,
    parent_id INT,
    INDEX par_ind (parent_id),
    FOREIGN KEY (parent_id)
        REFERENCES parent(id)
        ON DELETE CASCADE
--  !!!!!!!!!! MyIsam Engine неправильно
) ENGINE=MyIsam; 
show create table child;
/*!!! НЕТ FOREIGN KEY в таблице*/


Table
Create Table


child
CREATE TABLE `child` (
  `id` int(11) DEFAULT NULL,
  `parent_id` int(11) DEFAULT NULL,
  KEY `par_ind` (`parent_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1