Finding field values
I have a database that lists Air Handler air filter sizes and their quantities. The fields are Filter size 1, Filter size 2 and Filter size 3. The layout is arranged in list fashion so you have from left to right, Unit #, Location, Filter #1, Filter #1 Quantity, Filter #2, Filter #2 Quantity, Filter #3, Filter #3 Quantity.
The values in the Filter fields are all sizes of the various air filters used and the number fields are for the quantities used by a particular air handler, for instance, Air Handler Unit #1 uses 2 20X80 Link filters, so the Filter #1 value is 20X80 and the Filter #1 quantity is 2. Air Handler Units can have up to 3 different filter sizes, hence the Filter Size 1, 2 and 3.
What I'd like to do is generate a list of unique filter sizes and then the total quantity needed for each size in the database. It seems like a simple problem, but I've been unsuccessful finding a satisfactory solution yet.