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CREATE OR REPLACE PROCEDURE secure_dml
IS
BEGIN
IF TO_CHAR (SYSDATE, 'HH24:MI') NOT BETWEEN '08:00' AND '18:00'
OR TO_CHAR (SYSDATE, 'DY') IN ('SAT', 'SUN') THEN
RAISE_APPLICATION_ERROR (-20205,
'You may only make changes during normal office hours');
END IF;
END secure_dml;