The "dd" is a keyword argument to date functions (DATEADD, DATEDIFF) and it signifies the days to add for example. You could also add minutes, seconds, ...

What the whole thing...

Thanks for suggestion but as I mentioned I already tried all of it 0 reorganize/full scan, rebuild on non-clustered index and then on clustered again - all of which made...

I did not post the query as I can't post it as is and what I can post might not be useful at all. Find below a query with renamed...