SQL Server – How to Determine if Insert or Update in SQL Server 2008

insertsql-server-2008triggerupdate

Whenever INSERT is happened in the CUSTOMER table,I need to call the "StoredProcedure1"and
UPDATE is happend in the CUSTOMER table,I need to call the "StoredProcedure2" in the Trigger.
How to determine if insert or update in the trigger from SQL Server 2008.

Some one can please help me how to solve?

Code:

CREATE TRIGGER Notifications ON CUSTOMER
FOR INSERT,UPDATE
AS
BEGIN
DECLARE @recordId varchar(20);
set @recordId= new.Id;
    //if trigger is insert at the time I call to SP1
        EXEC StoredProcedure1 @recordId
    //if trigger is Upadeted at the time I call to SP2
        EXEC StoredProcedure2 @recordId
END

Best Answer

Since it's only UPDATE,INSERT you can say:

IF EXISTS (SELECT 1 FROM deleted)
  -- update
ELSE
  -- insert

You have a bigger problem, though. There is no such thing as new.Id, and an insert or update can affect multiple rows (in some platforms, triggers fire per row; in SQL Server, they fire per operation). So you need to either:

Use a loop to call the stored procedure for all of the RecordId values in inserted.
Stop using a stored procedure for this and perform whatever logic it does inside the trigger, as a set-based operation.

Related Solutions

Mysql – Trigger to UPDATE after UPDATE

Use a BEFORE trigger instead, and set the updated column assigning a value to NEW.updated (this would be a simple assignment, not an UPDATE). This way you won't trigger additional UPDATEs.

Your trigger body will simply look like

SET NEW.updated = NOW()

I usually use AFTER triggers only for modifying other tables, BEFORE for modifying the new (or updated) row, or suppress DELETE.

Handling Exceptions in Stored Procedures with Insert-Exec Blocks

The error in the EXEC part of the INSERT-EXEC statement is leaving your transaction in a doomed state.

If you PRINT out XACT_STATE() in the CATCH block it is set to -1.

Not all errors will set the state to this. The following check constraint error goes through to the catch block and the INSERT succeeds.

ALTER PROCEDURE test -- or create
AS
  BEGIN try
      DECLARE @retval INT;

      DECLARE @t TABLE(x INT CHECK (x = 0))

      INSERT INTO @t
      VALUES      (1)

      SET @retval = 0;

      SELECT @retval;

      RETURN( @retval );
  END try

  BEGIN catch
      PRINT XACT_STATE()

      PRINT ERROR_MESSAGE();

      SET @retval = -1;

      SELECT @retval;

      RETURN( @retval );
  END catch;

Adding this to the CATCH block

 IF (XACT_STATE()) = -1
BEGIN
    ROLLBACK TRANSACTION;
END;

Doesn't help. It gives the error

Cannot use the ROLLBACK statement within an INSERT-EXEC statement.

I don't think there is any way of recovering from such an error once it has happened. For your specific use case you don't need INSERT ... EXEC anyway though. You can assign the return value to a scalar variable then insert that in a separate statement.

DECLARE @RC INT;

EXEC sp_executesql
  N'EXEC @RC = test',
  N'@RC INT OUTPUT',
  @RC = @RC OUTPUT;

INSERT INTO @t
VALUES      (@RC)

Or of course you could restructure the called stored procedure so that it doesn't raise that error at all.

DECLARE @RetVal INT = -1

IF OBJECT_ID('PrintMax', 'P') IS NULL
  BEGIN
      EXEC('create procedure PrintMax as begin print ''hello world'' end;')

      SET @RetVal = 0
  END

SELECT @RetVal;

RETURN( @RetVal );

Best Answer

Related Solutions

Mysql – Trigger to UPDATE after UPDATE

Handling Exceptions in Stored Procedures with Insert-Exec Blocks

Related Question