I’ve been continuing with my Data Tales series up at sqlmag.com.
This time I’ve written about a pet hate: seeing code that counts rows when all it needs to do is to check for existence. However, all is not as bad as it seems because the optimizer does a pretty good job of protecting us from ourselves. (At least the SQL Server optimizer does )
It’s here: http://sqlmag.com/sql-server/data-tales-10-it-s-matter-existence