SQL Server/T-SQL/Trigger/Trigger Value — различия между версиями

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м (1 версия)
 
м (1 версия)
 
(нет различий)

Текущая версия на 10:20, 26 мая 2010

Get value from updated, inserted and deleted

1> create table employee(
2>     ID          int,
3>     name        nvarchar (10),
4>     salary      int,
5>     start_date  datetime,
6>     city        nvarchar (10),
7>     region      char (1))
8> GO
1>
2> insert into employee (ID, name,    salary, start_date, city,       region)
3>               values (1,  "Jason", 40420,  "02/01/94", "New York", "W")
4> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (2,  "Robert",14420,  "01/02/95", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (3,  "Celia", 24020,  "12/03/96", "Toronto",  "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (4,  "Linda", 40620,  "11/04/97", "New York", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (5,  "David", 80026,  "10/05/98", "Vancouver","W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (6,  "James", 70060,  "09/06/99", "Toronto",  "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (7,  "Alison",90620,  "08/07/00", "New York", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (8,  "Chris", 26020,  "07/08/01", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (9,  "Mary",  60020,  "06/09/02", "Toronto",  "W")
3> GO
(1 rows affected)
1>
2> select * from employee
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W
(9 rows affected)
1>
2> CREATE TABLE myArchive (
3>    AID         int           IDENTITY(1,1) PRIMARY KEY CLUSTERED,
4>    type        nvarchar(6)   NOT NULL,
5>    whenchanged smalldatetime NOT NULL DEFAULT Getdate(),
6>    ID int,
7>    newName nvarchar(30),
8>    oldName nvarchar(50)
9> )
10> GO
1>
2>
3> CREATE TRIGGER myTriggerINSERT
4> ON Employee
5> FOR INSERT
6> AS
7> DECLARE @ID int, @Name nvarchar(30)
8>
9> SET @ID = (SELECT ID FROM inserted)
10> SET @Name = (SELECT Name FROM inserted)
11>
12> INSERT myArchive (type, ID, newName) VALUES("INSERT", @ID, @Name)
13> GO
1>
2>
3> CREATE TRIGGER myTriggerDELETE
4> ON Employee
5> FOR DELETE
6> AS
7> DECLARE @ID int, @Name nvarchar(30)
8>
9> SET @ID = (SELECT ID FROM deleted)
10> SET @Name = (SELECT Name FROM deleted)
11>
12> INSERT myArchive (type, ID, oldName ) VALUES("DELETE", @ID, @Name)
13> GO
1>
2> CREATE TRIGGER myTriggerUPDATE
3> ON Employee
4> INSTEAD OF UPDATE
5> AS
6>
7> DECLARE @ID int, @newName nvarchar(30), @oldName nvarchar(30)
8>
9> IF (SELECT ID FROM inserted) <> (SELECT ID FROM deleted)
10>     RAISERROR ("You are not allowed to change ID.", 10,1)
11> ELSE
12> BEGIN
13>
14> --set local variables
15> SET @ID = (SELECT ID FROM inserted)
16> SET @newName = (SELECT Name FROM inserted)
17> SET @oldName = (SELECT Name FROM deleted)
18>
19> --write to table
20> UPDATE Employee SET Name = @newName WHERE ID = @ID
21> -- write to archive
22> INSERT myArchive (type, ID, newName, oldName) VALUES("UPDATE", @ID, @newName, @oldName)
23> END
24> GO
1>
2> INSERT Employee (id, name) VALUES (13, "Rickie")
3> GO
(1 rows affected)
1>
2> SELECT * FROM myArchive
3> GO
AID         type   whenchanged          ID          newName                        oldName
----------- ------ -------------------- ----------- ------------------------------ ------------------
          1 INSERT  2006-10-10 20:21:00          13 Rickie                         NULL
(1 rows affected)
1>
2> UPDATE Employee
3> SET Name = "Rick"
4> WHERE ID = 3
5> GO
(1 rows affected)
(1 rows affected)
1>
2> SELECT * FROM myArchive
3> GO
AID         type   whenchanged          ID          newName                        oldName
----------- ------ -------------------- ----------- ------------------------------ ------------------
          1 INSERT  2006-10-10 20:21:00          13 Rickie                         NULL
          2 UPDATE  2006-10-10 20:21:00           3 Rick                           Celia
(2 rows affected)
1>
2>
3> drop table myArchive
4> drop table employee
5> GO
1>



Learning to Reference Inserted and Deleted Tables

1> create table employee(
2>     ID          int,
3>     name        nvarchar (10),
4>     salary      int,
5>     start_date  datetime,
6>     city        nvarchar (10),
7>     region      char (1))
8> GO
1>
2> insert into employee (ID, name,    salary, start_date, city,       region)
3>               values (1,  "Jason", 40420,  "02/01/94", "New York", "W")
4> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (2,  "Robert",14420,  "01/02/95", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (3,  "Celia", 24020,  "12/03/96", "Toronto",  "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (4,  "Linda", 40620,  "11/04/97", "New York", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (5,  "David", 80026,  "10/05/98", "Vancouver","W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (6,  "James", 70060,  "09/06/99", "Toronto",  "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (7,  "Alison",90620,  "08/07/00", "New York", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (8,  "Chris", 26020,  "07/08/01", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (9,  "Mary",  60020,  "06/09/02", "Toronto",  "W")
3> GO
(1 rows affected)
1>
2> select * from employee
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W
(9 rows affected)
1>
2> --Learning to Reference Inserted and Deleted Tables
3>
4> IF EXISTS(SELECT *
5>     FROM sys.objects o JOIN sys.schemas s
6>     ON o.schema_id = s.schema_id
7>     WHERE type = "TR" AND
8>     s.name = "dbo" AND
9>     o.name = "myTrigger")
10>     DROP TRIGGER myTrigger
11> GO
1>
2> CREATE TRIGGER myTrigger
3> ON Employee
4> FOR UPDATE, INSERT, DELETE
5> AS
6> SELECT * FROM inserted
7> SELECT * FROM deleted
8> GO
1>
2> SELECT "Before INSERT"
3>
4> INSERT Employee (ID, Name)
5>     VALUES (31, "Rick")
6> GO
-------------
Before INSERT
(1 rows affected)
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
         31 Rick              NULL                    NULL NULL       NULL
(1 rows affected)
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
(0 rows affected)
1>
2> SELECT "Before UPDATE"
3>
4> UPDATE Employee
5> SET Name = "Rickie"
6> WHERE ID = 3
7> GO
-------------
Before UPDATE
(1 rows affected)
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          3 Rickie           24020 1996-12-03 00:00:00.000 Toronto    W
(1 rows affected)
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
(1 rows affected)
1> SELECT "Before DELETE"
2> GO
-------------
Before DELETE
(1 rows affected)
1> DELETE FROM Employee WHERE ID = 3
2> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
(0 rows affected)
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          3 Rickie           24020 1996-12-03 00:00:00.000 Toronto    W
(1 rows affected)
1> drop table employee
2> GO
1>