SQL Server 2005 implementation of MySQL REPLACE INTO?

Question

MySQL has this incredibly useful yet proprietary REPLACE INTO SQL Command.

Can this easily be emulated in SQL Server 2005?

Starting a new Trans

Answer 1

I wrote a blog post about this issue.

The bottom line is that if you want cheap updates and want to be safe for concurrent usage, try:

update t
set hitCount = hitCount + 1
where pk = @id

if @@rowcount < 1 
begin 
   begin tran
      update t with (serializable)
      set hitCount = hitCount + 1
      where pk = @id
      if @@rowcount = 0
      begin
         insert t (pk, hitCount)
         values (@id,1)
      end
   commit tran
end

This way you have 1 operation for updates and a max of 3 operations for inserts. So, if you are generally updating, this is a safe cheap option.

I would also be very careful not to use anything that is unsafe for concurrent usage. It's really easy to get primary key violations or duplicate rows in production.