触发器及序列结合实现自增字段

让oracle实现自增字段

先建序列,然后建立一个触发器实现!
cata0是表名,cata0_id是需要自增的字段!
CREATE SEQUENCE SEQ_cata0
INCREMENT BY 1
START WITH 1
MAXVALUE 9999999

CREATE TRIGGER TRG_cata0 BEFORE
INSERT ON cata0
FOR EACH ROW begin
   SELECT SEQ_cata0.NEXTVAL
     INTO :NEW.cata0_ID
     FROM DUAL;
End TRG_cata0;