Alter table to give foreign key constraint
问题 I have a table which has 2 columns which I copied from two different tables.What I want to do now is give a foreign key constraint on both the column names email and id shown below. ALTER TABLE users_role_map ADD CONSTRAINT FK_users_role_map FOREIGN KEY (email) REFERENCES usert(email), FOREIGN KEY (id) REFERENCES rolet(id) ON UPDATE CASCADE ON DELETE CASCADE; I get the following error: ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL