Designing a Warehouse Inventory System

A warehouse manager asks two questions at once. "How many of these do we have, and why does the system say 40 when the shelf has 38?"

The first question is easy to answer badly. The second one is why this design keeps a record of every movement, not just a number.

What the system must do

Keep a product catalogue, each product with its own code.

Know where stock physically sits, down to the shelf, not just the building.

Record every movement: goods arriving, goods picked, damage, and corrections after a count.