The check clause(Cont.) The check clause in SQL-92 permits domains to be restricted: Use check clause to ensure that an hourly_wage domain allows only values greater than a specified value. create domain hourly_wage numeric(5,2) constraint value_test check(value >4.00) The domain has a constraint that ensures that the hourly_wage is greater than 4.00 The clause constraint value_test is optional;useful to indicate which constraint an update violated. Database System Concepts,5th Edition,Oct 5.2006 4.13 Silberschatz,Korth and SudarshanDatabase System Concepts, 5th Edition, Oct 5. 2006 4.13 ©Silberschatz, Korth and Sudarshan The check clause (Cont.) The check clause in SQL-92 permits domains to be restricted: Use check clause to ensure that an hourly_wage domain allows only values greater than a specified value. create domain hourly_wage numeric(5,2) constraint value_test check(value > = 4.00) The domain has a constraint that ensures that the hourly_wage is greater than 4.00 The clause constraint value_test is optional; useful to indicate which constraint an update violated