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• CASCADE: Delete or update the row from the parent table and automatically delete or update the matching rows in the child table. ON DELETE CASCADE is supported starting from MySQL 3.23.50 and ON UPDATE CASCADE is supported starting from 4.0.8. Between two tables, you should not define several ON UPDATE CASCADE clauses that act on the same column in the parent table or in the child table. 
• SET NULL: Delete or update the row from the parent table and set the foreign key column or columns in the child table to NULL. This is valid only if the foreign key columns do not have the NOT NULL qualifier specified. ON DELETE SET NULL is available starting from MySQL 3.23.50 and ON UPDATE SET NULL is available starting from 4.0.8. 
If you specify a SET NULL action, make sure that you have not declared the columns in the child table as NOT NULL. 
• NO ACTION: In standard sQL, NO ACTION means no action in the sense that an attempt to delete or update a primary key value will not be allowed to proceed if there is a related foreign key value in the referenced table. Starting from 4.0.18 InnoDB rejects the delete or update operation for the parent table. 
• RESTRICT: Rejects the delete or update operation for the parent table. NO ACTION and RESTRICT are the same as omitting the ON DELETE or ON UPDATE clause. (Some database systems have deferred checks, and NO ACTION is a deferred check. In MySQL, foreign key constraints are checked immediately, so NO ACTION and RESTRICT are the same.) 
• SET DEFAULT: This action is recognized by the parser, but InnoDB rejects table definitions containing ON DELETE SET DEFAULT or ON UPDATE SET DEFAULT clauses.

mysqldump -u[USERNAME] -p[PASSWORD] --add-drop-table --no-data [DATABASE] | grep ^DROP | mysql -u[USERNAME] -p[PASSWORD] [DATABASE]