What happens in a trigger stays in the transaction: T-SQL Tuesday #106

Kenneth Fisher, 2018-09-11

Anything that happens in a trigger happens within the same transaction of the command that called it.

Part of me feels like this should be pretty obvious but it’s also one of those things that’s so obvious that it becomes easy to miss.

Let me explain:

If you run an UPDATE on a table and a trigger is fired then the UPDATE statement will not be completed until everything within that trigger finishes. If the trigger fails (throws an error) then the UPDATE statement will fail and roll back. And of course, if that UPDATE statement is part of a transaction then the transaction’s time/failure is affected by the trigger. So if you have a trigger that takes, say 1 second to run (which seems pretty quick right?) and then you have a transaction that runs 1000 commands that fire that trigger. Guess what? That transaction just had 1000 seconds added to it. Because of this, one of the many trigger best practices is to make sure that your triggers are as fast as possible.

T-SQL TuesdayNow, this post is my entry for the blog party T-SQL Tuesday. Our host this month , and the new supervisor(?) for T-SQL Tuesday, is Steve Jones (b/t). His topic is Trigger Headaches or Happiness. His invite seemed to invite a story, so here’s mine.


  1. We have an application that has a trigger on a table.
  2. The trigger has a cursor that loops through all of the inserts/updates.
  3. The code in the cursor runs a stored procedure for each insert/update.
  4. The stored procedure is on the other side of a linked server.
  5. The code in the stored procedure calls several local tables, and a table across a linked server .. back to the original server.


And then I get called because a 100 row update takes a long time. *sigh*





Related content

Database Mirroring FAQ: Can a 2008 SQL instance be used as the witness for a 2005 database mirroring setup?

Question: Can a 2008 SQL instance be used as the witness for a 2005 database mirroring setup? This question was sent to me via email. My reply follows. Can a 2008 SQL instance be used as the witness for a 2005 database mirroring setup? Databases to be mirrored are currently running on 2005 SQL instances but will be upgraded to 2008 SQL in the near future.

Robert Davis


1,567 reads

Networking – Part 4

You may want to read Part 1 , Part 2 , and Part 3 before continuing. This time around I’d like to talk about social networking. We’ll start with social networking. Facebook, MySpace, and Twitter are all good examples of using technology to let…

Andy Warren


1,530 reads

Speaking at Community Events – More Thoughts

Last week I posted Speaking at Community Events – Time to Raise the Bar?, a first cut at talking about to what degree we should require experience for speakers at events like SQLSaturday as well as when it might be appropriate to add additional focus/limitations on the presentations that are accepted. I’ve got a few more thoughts on the topic this week, and I look forward to your comments.

Andy Warren


360 reads