The world's most popular open source database
The Foreign Keys tab is organized in much the
same fashion as the Indexes tab and adding or
editing a foreign key is similar to adding or editing an index.
To add a foreign key, click the last row in the Foreign
Key Name list. Enter a name for the foreign key and
select the column or columns that you wish to index by checking
the column name in the Column list. You can
remove a column from the index by removing the check mark from
the appropriate column.
Under Foreign Key Options choose an action for the update and delete events.
The options are:
RESTRICT
CASCADE
SET NULL
NO ACTION
To drop a foreign key, right click the row you wish to delete and then select the Delete Selected FKs menu option.
To modify any of the properties of a foreign key, simply select it and make the desired changes.

