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Trigger :old and :new concept

 


CREATE TABLE AUDIT_EMP 

(RCD DATE, EMPID NUMBER(4), old_salary NUMBER(7,2), new_salary NUMBER(7,2)

);



SELECT * FROM AUDIT_EMP;



CREATE OR REPLACE TRIGGER audit_emp_values

    AFTER DELETE OR INSERT OR UPDATE ON emp

    FOR EACH ROW

    BEGIN

    INSERT INTO audit_emp

    VALUES ( SYSDATE, :OLD.empno,:OLD.sal, :NEW.sal );

   END;



UPDATE EMP SET SAL = SAL+100 WHERE EMPNO =7369;


SELECT * FROM AUDIT_EMP;



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