[AccessD] Optimizing query when select part requires a calculation

Pursuant to IN(). An often-preferred alternative is to create a temp-table
consisting of the values contained within the IN(), and then to join this to
the real tables. The time taken to construct the temp-table is negligible.
Once it's created, the natural joins do all the heavy lifting for you.

Since you want to join on multiple columns, I suggest that you create a
calculated (virtual) column on both tables, and then do the join on those
columns. It might require a little addition to your documentation, but it
cleans up the mess rather nicely, IMO.

HTH,
Arthur