Inventory Management application can become extremely complex. Basically your stock on hand is Opening stock plus receipts minus issues. This is the overriding principle.
So you have 200 fish in stock, You take an order for 100. You still have 200 in stock until you take the 100 out of stock. Just because you have an order does not necessarily reduce you actual stock. To make have a stock allocation situation whereby your Available to Promise stock is reduced Sounds simple but it aint basically.
Most MRPII systems that deal with stock base it on transactions.
Receipt transaction Goods delivered to you
Issue Transaction Goods taken from stock for whatever reason
Adjustment Transaction, Used for putting stock figure right when it gets screwed up.
There are several threads on this subject and I suggest you review these.
Basically the Doc Man suggests you model your requirements first using post-its and a wall. Its good advice. You are entering an area that quickly and easily becomes a very complex, processor heavy application.
Think it out completely first
Len B
