Creating a Dual entry in one table for multiple location inventory.
I'm new to filemaker, but I'm slowly getting places. I'm creating a multiple location inventory system where items in inventory can be placed in different locations and the inventory will be able to tell the user which items and how many are in each location. I'm planning on using an item transaction table to keep track of all movements of inventory with a field for location, qty in and qty out. My problem now is moving an item from one location to another. I know that what I need to do is create a dual entry in this table. One entry for which location and Qty out and one entry for which location and Qty in. I just can't figure out how to go about doing this. In an ideal world I would like to create one from with a field for Item being moved, Qty Move from location drop down and move to location drop down.
Any advice on how to tackle this problem would be greatly appreciated it's starting to hurt my head.