Is this the right way how to make a trigger in Oracle?
CREATE OR REPLACE TRIGGER "TRI_AMOUNT_REDUCTION" BEFORE INSERT ON "PURCHASE" FOR EACH ROW BEGIN IF (:NEW.CLIENTNO =SELECT C.CNAME, T.CLIENTNO, T.TOTAL FROM CLIENT C, ( SELECT A.* FROM (SELECT CLIENTNO, SUM(AMOUNT) AS TOTAL FROM PURCHASE GROUP BY CLIENTNO) A,(SELECT MAX(B.TOTAL) AS TOP FROM(SELECT CLIENTNO, SUM(AMOUNT) AS TOTAL FROM PURCHASE GROUP BY CLIENTNO)B)C WHERE A.TOTAL=C.TOP) T WHERE C.CLIENTNO = T.CLIENTNO; ) THEN :NEW.AMOUNT := AMOUNT - (AMOUNT * 0.1); END IF; END; /
When I run this script, the server says "the trigger created with compilation errors"... I don't know what that exactly means