2013-01-31
今天学习了点oracle，触发器的简单使用，需要解决的问题是如下，还是英文描述吧。
the triggers are perfect is change auditing.The example is of Paranoid Pam(who runs a bowling alley and have been receiving complaints about people cheating on their scores).she recently complete an oracle application to catch the cheaters.
simply say, she just want to find who and when and how change the data.
next, you will say my PL/SQL code.in the write i have use some may useful method to make it.
souce code:
1
--
好的创建表的方法
2
DECLARE
3
TB
NUMBER
;
4
BEGIN
5
SELECT
COUNT
(
*
)
INTO
TB
FROM
TABS
WHERE
TABLE_NAME
=
'
FRAME
'
;
6
IF
TB
<>
0
THEN
7
EXECUTE
IMMEDIATE
'
DROP TABLE frame
'
;
8
EXECUTE
IMMEDIATE
'
9
CREATE TABLE frame
10
(
11
bowler_id number,
12
game_id number,
13
frame_id number,
14
strike varchar2(1) default
''
N
''
,
15
spare varchar2(1) default
''
N
''
,
16
score number,
17
constraint frame_pk
18
primary key (bowler_id,game_id,frame_id)
19
)
'
;
20
DBMS_OUTPUT.PUT_LINE(
'
存在该表已删除，并创建新的表
'
);
21
ELSE
22
EXECUTE
IMMEDIATE
'
CREATE TABLE frame
23
(
24
bowler_id number,
25
game_id number,
26
frame_id number,
27
strike varchar2(1) default
''
N
''
,
28
spare varchar2(1) default
''
N
''
,
29
score number,
30
constraint frame_pk
31
primary key (bowler_id,game_id,frame_id)
32
)
'
;
33
DBMS_OUTPUT.PUT_LINE(
'
不存在该表，已创建新表
'
);
34
END
IF
;
35
END
;
36
37
--
创建审计表
38
DECLARE
39
TB
NUMBER
;
40
BEGIN
41
SELECT
COUNT
(
*
)
INTO
TB
FROM
TABS
WHERE
TABLE_NAME
=
'
FRAME_AUDIT
'
;
42
IF
TB
<>
0
THEN
43
EXECUTE
IMMEDIATE
'
DROP TABLE frame_audit
'
;
44
EXECUTE
IMMEDIATE
'
45
CREATE TABLE frame_audit
46
(
47
bowler_id NUMBER,
48
game_id NUMBER,
49
frame_id NUMBER,
50
old_strike VARCHAR2(1),
51
new_strike VARCHAR2(1),
52
53
old_spare VARCHAR2(1),
54
new_spare VARCHAR2(1),
55
56
old_score VARCHAR2(1),
57
new_score VARCHAR2(1),
58
59
change_date DATE,
60
operation VARCHAR2(6)
61
)
'
;
62
DBMS_OUTPUT.PUT_LINE(
'
存在该表已删除，并创建新的表
'
);
63
ELSE
64
EXECUTE
IMMEDIATE
'
CREATE TABLE frame_audit
65
(
66
bowler_id NUMBER,
67
game_id NUMBER,
68
frame_id NUMBER,
69
old_strike VARCHAR2(1),
70
new_strike VARCHAR2(1),
71
72
old_spare VARCHAR2(1),
73
new_spare VARCHAR2(1),
74
75
old_score VARCHAR2(1),
76
new_score VARCHAR2(1),
77
78
change_date DATE,
79
operation VARCHAR2(6)
80
)
'
;
81
DBMS_OUTPUT.PUT_LINE(
'
不存在该表，已创建新表
'
);
82
END
IF
;
83
END
;
84
85
86
--
创建触发器
87
CREATE
OR
REPLACE
TRIGGER
audit_frames
88
AFTER
INSERT
OR
UPDATE
OR
DELETE
ON
frame
89
FOR
EACH ROW
90
BEGIN
91
IF
inserting
THEN
92
INSERT
INTO
frame_audit(bowler_id,game_id,frame_id,
93
new_strike,new_spare,
94
new_score,change_date,operation)
95
VALUES
(:new.bowler_id,:new.game_id,:new.frame_id,:new.strike,:new.spare,:new.score,SYSDATE,
'
insert
'
);
96
97
ELSIF updating
THEN
98
INSERT
INTO
frame_audit(bowler_id,game_id,frame_id,
99
old_strike,new_strike,old_spare,new_spare,
100
old_score,new_score,change_date,operation)
101
VALUES
(:new.bowler_id,:new.game_id,:new.frame_id,:old.strike,:new.strike,:old.spare,:new.spare,:old.score,:new.score,SYSDATE,
'
update
'
);
102
103
ELSIF deleting
THEN
104
INSERT
INTO
frame_audit(bowler_id,game_id,frame_id,
105
old_strike,old_spare,
106
old_score,change_date,operation)
107
VALUES
(:old.bowler_id,:old.game_id,:old.frame_id,:old.strike,:old.spare,:old.score,SYSDATE,
'
insert
'
);
108
109
END
IF
;
110
END
audit_frames;
111
112
--
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
113
--
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。
114
115
116
INSERT
INTO
frame (bowler_id,game_id,frame_id,strike)
117
VALUES
(
1
,
2
,
3
,
'
y
'
);
118
119
120
SELECT
*
FROM
frame;
121
122
UPDATE
frame
SET
strike
=
'
N
'
,
123
spare
=
'
y
'
124
WHERE
bowler_id
=
1
125
AND
game_id
=
2
126
AND
frame_id
=
3
;
127
128
DELETE
frame
WHERE
bowler_id
=
1
;
129
130
COMMIT
;
131
132
SELECT
*
FROM
frame;
133
134
SELECT
*
FROM
frame_audit;
代码可以放在pl/sql的sql脚本中运行，可以看到相应的结果。
