Question

This is a question same as ON DELETE CASCADE not working in MySQL question where the My-ISAM engine is not doing its ON DELETE CASCADE part. But the problem is i have to use MyISAM table type itself and not InnoDB

How can i ensure that i can simulate the ON DELETE CASCADE when ever a row gets deleted in my parent table, so that its updated in many other tables it is referencing it.? Can i write some kind of trigger?

Answer 1

From the fine manual:

For other storage engines, MySQL Server parses and ignores foreign key specifications.

So if you need ON DELETE CASCADE behavior and MyISAM tables at the same time then you’ll have to do the CASCADE part by hand with a DELETE trigger or something similar outside the database. Adding a trigger like this should work:

create trigger fake_cascade_delete after delete on table_name
for each row begin
    delete from other_table
    where referencing_column = OLD.id;
end;

That’s just off the top of my head and the table and column names are, of course, just for demonstration purposes.