How to prevent the deletion of foreign key child records?

Question

MySQL

Hello. There are 2 tables (A-B), and they are connected by fk (foreign key) by one field. How can I make sure that when deleting a parent key using ON DELETE CASCADE, the child key is not deleted, and the record remains in the table?
You need to bring the base to 3NF

Answer 1

ON DELETE dev.mysql.com/doc/refman/5.7/en/create-table-forei...