I have a file that I use to manage purchase orders. I want to have a field that calculates the total quantity of a certain product. ie on an order that has 3 different items I need a total quantity count on only the items that have the item# 13063. I'm sure this is easily done, but I am not very conversant with calculations unless they are very simple. Any help I could get would be greatly appreciated.

Is it always going to be that specific item number? If so, you can create a second line item relationship (call it "LineItem13063") with the same criteria as your existing relationship, plus the added condition that item# = 13063, and then use the count function.

Count(LineItem13063::AnyField)

No there are about 5 different item numbers that this will apply to

That's a small enough number that you could build a relationship for each one.

Similar to the previous solution.

Define a global field on the main table, this field will have a value list with the 5 different item numbers.

Then define a relationship from the main table to the line items

using gItemNumber = lineitem_itemNumber

And then the calc could be:

Count ( g_ItemNumber::item_number )

Hope it helps!

Everytime you select a different item number from the list you will get the count of how many orders have that particular item.