Question

I have set foreign key integrity in a table. But i am able to delete data from the master table, which is reference in child table..
What would be the problem
Actually it should say error on deletion like all referenced table data has to be deleted.

Answer 1

Did you specify ON DELETE CASCADE ? when you created your FK? Don’t know which engine you are using either

example

CREATE TABLE parent (id INT NOT NULL,
                     PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE child (id INT, parent_id INT,
                    INDEX par_ind (parent_id),
                    FOREIGN KEY (parent_id) REFERENCES parent(id)
                      ON DELETE CASCADE
) ENGINE=INNODB;

More here http://dev.mysql.com/doc/refman/5.1/en/innodb-foreign-key-constraints.html