How to undo cascading deletion by foreign key?

Question

MySQL

Table creation:

CREATE TABLE book (
    book_id INT PRIMARY KEY AUTO_INCREMENT,    
    title VARCHAR(50),
    author_id INT,
    genre_id INT,
    price DECIMAL(8, 2),
    amount INT,
    FOREIGN KEY (author_id)  REFERENCES author (author_id) ON DELETE CASCADE,
    FOREIGN KEY (genre_id)  REFERENCES genre (genre_id) ON DELETE SET NULL
 );

How, with the help of another query, when deleting information from one table, cancel the cascading deletion in the related one?

Answer 1

Only change the link property to ON DELETE SET NULL.

Answer 2

Delete and create again. Documentation .

Answer 3

SET foreign_key_checks = 0;
but I won't say. google