Question

How does the ON-DELETE-CASCADE statement work?

Answer 1

Using this On Delete Cascade you can automatically delete a record in the child table when the same record is deleted from the parent table. This statement can be used with Foreign Keys as well.

You can add this On Delete Cascade option on an existing table.

Syntax:

Alter Table Child_T1 ADD Constraint Child_Parent_FK References

Parent_T1(Column1) ON DELETE CASCADE;