What are the different ways to maintain data integrity in a child table when records in the parent table are deleted?

When two tables are connected through a foreign key and the data in the parent table is deleted, if the record also exists in the child table, you can maintain it in the following ways Data Integrity:

Cascade Delete

If the value of a foreign key is deleted from the main table, this option will also delete the record from the child table.

Null Delete

If the value of the foreign key is deleted from the main table, this option will set all values ​​of the record in the child table to NULL.

The above is the detailed content of What are the different ways to maintain data integrity in a child table when records in the parent table are deleted?. For more information, please follow other related articles on the PHP Chinese website!