Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.databases.ms-sqlserver > #155

Re: SSE 2008: Trigger: Modifying Data to be Written

Cross-posted to 2 groups.

Show all headers | View raw

On Sat, 09 Apr 2011 11:22:07 +0200, Erland Sommarskog
<esquel@sommarskog.se> wrote:

>Gene Wirchenko (genew@ocis.net) writes:
>>      Thank you. I found an example of INSTEAD OF myself shortly after
>> posting.  Half the battle of learning SQL Server is knowing exactly
>> what to ask for, and sometimes, it is the tougher half!
> 
>I like to add that many developers would prefer to do this with an AFTER 
>trigger. This means a higher overhead, because the bad data is first 
>written to the table, and then you need to update the target table.
>On the other hand, INSTEAD OF triggers gives you a maintainability 
>problem. Since you need to redo the original statement, you need to
>update the trigger every time you add a column to the table. If you 
>forget you may get some headache sorting out what is going on.

  1) Part of adding a column would be considering whether it needs
this adjusting and so to add its handling to the trigger.

  2) I think that maintainability was covered by the code I borrowed
from.  My derivative has
          select * into #Inserted from Inserted
at the beginning and then at the end, writes with
          insert into Accounts select * from #Inserted

>What you really want is a BEFORE trigger where you can modify inserted.
>But unfortunately SQL Server does not have BEFORE triggers.

Sincerely,

Gene Wirchenko

Back to comp.databases.ms-sqlserver | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

SSE 2008: Trigger: Modifying Data to be Written Gene Wirchenko <genew@ocis.net> - 2011-04-08 15:11 -0700
  Re: SSE 2008: Trigger: Modifying Data to be Written "Bob Barrows" <reb01501@NOSPAMyahoo.com> - 2011-04-08 18:44 -0400
    Re: SSE 2008: Trigger: Modifying Data to be Written Gene Wirchenko <genew@ocis.net> - 2011-04-08 16:23 -0700
      Re: SSE 2008: Trigger: Modifying Data to be Written Erland Sommarskog <esquel@sommarskog.se> - 2011-04-09 11:22 +0200
        Re: SSE 2008: Trigger: Modifying Data to be Written Gene Wirchenko <genew@ocis.net> - 2011-04-09 21:29 -0700
          Re: SSE 2008: Trigger: Modifying Data to be Written Erland Sommarskog <esquel@sommarskog.se> - 2011-04-10 14:48 +0200
            Re: SSE 2008: Trigger: Modifying Data to be Written Gene Wirchenko <genew@ocis.net> - 2011-04-11 09:46 -0700
          Re: SSE 2008: Trigger: Modifying Data to be Written "Bob Barrows" <reb01501@NOSPAMyahoo.com> - 2011-04-10 08:54 -0400
            Re: SSE 2008: Trigger: Modifying Data to be Written Erland Sommarskog <esquel@sommarskog.se> - 2011-04-10 21:33 +0200
            Re: SSE 2008: Trigger: Modifying Data to be Written Gene Wirchenko <genew@ocis.net> - 2011-04-11 09:42 -0700
              Re: SSE 2008: Trigger: Modifying Data to be Written "Bob Barrows" <reb01501@NOyahooSPAM.com> - 2011-04-11 14:55 -0400
                Re: SSE 2008: Trigger: Modifying Data to be Written Gene Wirchenko <genew@ocis.net> - 2011-04-11 14:53 -0700
                Re: SSE 2008: Trigger: Modifying Data to be Written "Bob Barrows" <reb01501@NOSPAMyahoo.com> - 2011-04-11 18:49 -0400

csiph-web