please does anybody who has indept knowlege on oracle and mysql tell me how add check constraints to the database? thanks

Browse google for that pally

It depends,u add a check constraint to a table.either at the time of creation of the table or after creation.u can do that with enterprise manager.edit the table add the constraint.or see an example in sql.
ALTER TABLE employees ADD CONSTRAINT
validate_hire_date CHECK
(hire_date > TO_DATE('15-Apr-1999','DD-Mon-YYYY'));

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