Question

How can I prevent locking issues between two triggers that fires at the same event on the same table?

The DB I’m working on has already one update trigger that is encrypted and therefore I cannot modify it. I made another update trigger to accomplish some new tasks, it’s working correctly when I test it directly on the database, but fails when I make an update to a product on the front-end application. Apparently, when I have my trigger active both triggers fails. The message I get is something like "Document is already open, I’ll increment it’s value".

Is this a locking issue?

There’s a related question where someone says we can have more than one trigger (for same event) on a table.

Here’s my triggers code:

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

CREATE TRIGGER [dbo].[tr_st_rep_update]
ON [dbo].[st]
AFTER UPDATE
AS
  BEGIN
      SET NOCOUNT ON;

      IF ( update(ref)
            OR update(design)
            OR update(u_update)
            OR update(u_ativo)
            OR update(stock)
            OR update(epv1)
            OR update(epv2)
            OR update(epv3)
            OR update(peso)
            OR update(u_catnv1)
            OR update(u_catnv2)
            OR update(u_catnv3)
            OR update(u_dpromoi)
            OR update(u_dpromof)
            OR update(u_destaque) )
        BEGIN
            IF (SELECT count(*)
                FROM   Inserted
                       INNER JOIN Deleted
                         ON Inserted.ststamp = Deleted.ststamp
                WHERE  inserted.u_ativo = 1
                        OR ( Deleted.u_ativo = 1
                             AND Inserted.u_ativo = 0 )) > 0
              BEGIN
                  INSERT INTO RepData
                              (id,
                               REF,
                               familia,
                               stock,
                               epv1,
                               epv2,
                               epv3,
                               peso,
                               u_accao,
                               imagem,
                               process)
                  SELECT Inserted.ststamp AS id,
                         Inserted.REF     AS REF,
                         Inserted.familia AS familia,
                         Inserted.stock   AS stock,
                         Inserted.epv1    AS epv1,
                         Inserted.epv2    AS epv2,
                         Inserted.epv3    AS epv3,
                         Inserted.peso    AS peso,
                         CASE
                           WHEN Deleted.u_ativo = 1
                                AND Inserted.u_ativo = 0 THEN 'd'
                           ELSE 'u'
                         END              AS u_accao,
                         Inserted.imagem  AS imagem,
                         0                AS process
                  FROM   Inserted
                         INNER JOIN Deleted
                           ON Deleted.ststamp = Inserted.ststamp
                  WHERE  inserted.u_ativo = 1
                          OR ( Deleted.u_ativo = 1
                               AND Inserted.u_ativo = 0 )
              END
        END
  END 

Any help would be appreciated.

Update: Database is MSSQL 2008

Answer 1

Problem solved.

I really don’t know the source of the problem although I think it’s something related to table locking, in this case the on the Inserted table.

I just changed the inner select statement so that I grab the values directly from the st table instead of the Inserted.

Thanks everyone.