Oracle触发器的简单使用

--好的创建表的方法
DECLARE
TB NUMBER;
BEGIN
SELECT COUNT(*) INTO TB FROM TABS WHERE TABLE_NAME = 'FRAME';
IF TB <> 0 THEN
EXECUTE IMMEDIATE 'DROP TABLE frame';
EXECUTE IMMEDIATE '
CREATE TABLE frame
(
bowler_id number,
game_id number,
frame_id number,
strike varchar2(1) default ''N'',
spare varchar2(1) default ''N'',
score number,
constraint frame_pk
primary key (bowler_id,game_id,frame_id)
)';
DBMS_OUTPUT.PUT_LINE('存在该表已删除，并创建新的表');
ELSE
EXECUTE IMMEDIATE 'CREATE TABLE frame
(
bowler_id number,
game_id number,
frame_id number,
strike varchar2(1) default ''N'',
spare varchar2(1) default ''N'',
score number,
constraint frame_pk
primary key (bowler_id,game_id,frame_id)
)';
DBMS_OUTPUT.PUT_LINE('不存在该表，已创建新表');
END IF;
END;

--创建审计表
DECLARE
TB NUMBER;
BEGIN
SELECT COUNT(*) INTO TB FROM TABS WHERE TABLE_NAME = 'FRAME_AUDIT';
IF TB <> 0 THEN
EXECUTE IMMEDIATE 'DROP TABLE frame_audit';
EXECUTE IMMEDIATE '
CREATE TABLE frame_audit
(
bowler_id NUMBER,
game_id NUMBER,
frame_id NUMBER,
old_strike VARCHAR2(1),
new_strike VARCHAR2(1),

old_spare VARCHAR2(1),
new_spare VARCHAR2(1),

old_score VARCHAR2(1),
new_score VARCHAR2(1),

change_date DATE,
operation VARCHAR2(6)
)';
DBMS_OUTPUT.PUT_LINE('存在该表已删除，并创建新的表');
ELSE
EXECUTE IMMEDIATE 'CREATE TABLE frame_audit
(
bowler_id NUMBER,
game_id NUMBER,
frame_id NUMBER,
old_strike VARCHAR2(1),
new_strike VARCHAR2(1),

old_spare VARCHAR2(1),
new_spare VARCHAR2(1),

old_score VARCHAR2(1),
new_score VARCHAR2(1),

change_date DATE,
operation VARCHAR2(6)
)';
DBMS_OUTPUT.PUT_LINE('不存在该表，已创建新表');
END IF;
END;

--创建触发器
CREATE OR REPLACE TRIGGER audit_frames
AFTER INSERT OR UPDATE OR DELETE ON frame
FOR EACH ROW
BEGIN
IF inserting THEN
INSERT INTO frame_audit(bowler_id,game_id,frame_id,
new_strike,new_spare,
new_score,change_date,operation)
VALUES(:new.bowler_id,:new.game_id,:new.frame_id,:new.strike,:new.spare,:new.score,SYSDATE,'insert');

ELSIF updating THEN
INSERT INTO frame_audit(bowler_id,game_id,frame_id,
old_strike,new_strike,old_spare,new_spare,
old_score,new_score,change_date,operation)
VALUES(:new.bowler_id,:new.game_id,:new.frame_id,:old.strike,:new.strike,:old.spare,:new.spare,:old.score,:new.score,SYSDATE,'update');

ELSIF deleting THEN
INSERT INTO frame_audit(bowler_id,game_id,frame_id,
old_strike,old_spare,
old_score,change_date,operation)
VALUES(:old.bowler_id,:old.game_id,:old.frame_id,:old.strike,:old.spare,:old.score,SYSDATE,'insert');

END IF;
END audit_frames;

--在创建之后，后来使用的时候报了一个触发器无效且未通过认证的错误
--解决办法是找到触发器-》右键查看-》找到相应的错误（insert->inserting）.问题解决。

INSERT INTO frame (bowler_id,game_id,frame_id,strike)
VALUES (1,2,3,'y');

SELECT * FROM frame;

UPDATE frame SET strike ='N',
spare = 'y'
WHERE bowler_id =1
AND game_id =2
AND frame_id =3;

DELETE frame WHERE bowler_id = 1;

COMMIT;

SELECT * FROM frame;

SELECT * FROM frame_audit;