Thanks Chris, that helps a lot!

So I'm understanding now that starting at 0 and ending at the difference [ie. DATEDIFF(hh,0,@EndDT-@StartDT)] allows the query to work when the hour...

Thanks for the article. I appreciate it.

One question though. It said in the article

It’s important that the DATEDIFF in the formula have a "starting date" of "0" (the numeric...