Question

I want to check a Column value when update.If its match insert into another table.
My Tables:

My trigger:

CREATE TRIGGER tr_test
ON test1
FOR UPDATE
AS
    SET nocount ON

    IF ( Update(sname) )
      DECLARE @Name NVARCHAR

    DECLARE @id INT

    SET @id=@@IDENTITY 
    SET @Name=(SELECT sname
               FROM   test1
               WHERE  id = @id)

    IF( @Name = 'Paras' )
      BEGIN
          INSERT INTO test2
                      (loginfo)
          VALUES     ('success')
      END  

And my update query is:

update Test1 set Sname='Paras' where ID=1

When I run this update query Nothing is happen.Test2 table is empty.I think problem is @@IDENTITY but not sure.Thanks.

Answer 1

Try this:

CREATE TRIGGER tr_test
ON test1
FOR UPDATE
AS
    SET nocount ON

    IF ( Update(sname) )
      DECLARE @Name NVARCHAR

    DECLARE @id INT

    SET @id=(select id from inserted) 
    SET @Name=(SELECT sname
               FROM   inserted
               WHERE  id = @id)

    IF( @Name = 'Paras' )
      BEGIN
          INSERT INTO test2
                      (loginfo)
          VALUES     ('success')
      END  

But it’s better to do this, an update can update many rows, the above will fail if UPDATE matches many rows, use EXISTS:

CREATE TRIGGER tr_test
ON test1
FOR UPDATE
AS
    SET nocount ON

    IF( EXISTS(select * From inserted where sname = 'Paras' ) )
      BEGIN
          INSERT INTO test2
                      (loginfo)
          VALUES     ('success')
      END  

inserted table is the name of the table where the UPDATE’s new values goes, deleted table is the name of the table where UPDATE’s old values goes