Does an update trigger an INSERT event as all updates are DELETE + (re)INSERT in SQL Server

Question

As I understand it, when you update one or more rows in SQL Server, the record is deleted and reinserted with the new values. Does this therefore mean that an INSERT event

Answer 1

I think that (the split into delete + insert) is only true when the update requires the index to be updated. See this link:

http://www.sqlservercentral.com/blogs/sqlinthewild/2011/06/21/are-all-updates-split-into-delete_2D00_insert_3F00_/

and particularly the last paragraph:

Now we do have a split update. We’ve got a delete_rows and an insert_rows operation in the log. This was not done as an in-place update So what can we conclude here? Does SQL do all updates as split updates? It should be clear that, for cases where the index key is not changed, SQL can do updates as in-place updates. I’m not going to try and claim that it always will, that would be silly, there are lots of scenarios that I haven’t looked at (page splits and forwarded rows being among the most obvious), but it can and will do in-place updates. For updates that change the key values, SQL will not do those as in-place updates. Paul explained that in one of his debunking posts a while back – http://sqlskills.com/BLOGS/PAUL/post/Do-changes-to-index-keys-really-do-in-place-updates.aspx