RDBMS PLSQL Program 46 program to generate before insert,update and delete row trigger on emp table which will not allow changes in data before and after office hours using RAISE_APPLICATION_ERROR() function

 CREATE OR REPLACE TRIGGER Working_hrs

BEFORE INSERT OR UPDATE OR DELETE ON emp

DECLARE

WORKING_HOURS NUMBER(2);

BEGIN

WORKING_HOURS := TO_CHAR(SYSDATE,’HH24′);

IF WORKING_HOURS < 9 AND WORKING_HOURS > 17 THEN

RAISE_APPLICATION_ERROR(-20001,'Its not official working hours! Can not do operations on emp');

END IF;

END;

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