Inventory and warehouses

Inventory is held per product, warehouse, bin and lot, with serial numbers where needed. Each position shows quantity on hand, quantity allocated and a quality status: Available, Quarantine, Hold or Expired. Warehouses carry a code, address, type (distribution center, hub, cross-dock, raw, WIP, finished goods, quarantine or 3PL), time zone and manager. Bins carry a zone (receiving, reserve, pick, pack, ship or quarantine), a type and capacity by volume and weight.

Every physical change is a stock movement: receipt, putaway, issue, transfer, pick, ship, scrap, adjustment or return in, with quantity, date, operator, from and to locations and the reference that caused it. Allocations commit on-hand stock to a shipment, production order or transfer and move from Soft to Hard, Picked and Released. Transfers move stock between warehouses from Draft through Approved and In Transit to Received.

• Position by bin and lot. Stock is tracked where it sits, by lot, with its quality status.
• Every change is a movement. Quantities change only through recorded movements with a reference.
• Allocate before picking. Stock is allocated to demand before it is picked, so available stock is never promised twice.

Agree the bin layout and zones for each warehouse before loading stock. Agree which products are lot or serial controlled. Agree when stock moves to Quarantine or Hold and who releases it. Agree when allocations become hard and who may release them. Decide the approval for inter-warehouse transfers.

After putaway, the Dallas warehouse shows 1,080 bags of lot R-2602 in reserve bin R-14-03, Available. A customer order for 600 bags is allocated softly, then hard once the pick date is set. The operator picks from R-14-03, the allocation moves to Picked and a Pick movement is recorded. The remaining 480 stay Available.

The Houston warehouse runs short, and the Inventory Manager approves a transfer of 200 bags. A Transfer movement records the move out of Dallas; on arrival in Houston the transfer is Received and a putaway movement records the bin.

• Inventory On Hand — Stock by product, warehouse, bin and lot with on-hand, allocated and quality status.
• Transfers in Flight — Approved and in-transit transfers with ship and arrival dates.

• Allocation to delivered shipment: Allocate, pick and ship.
• Cycle count to adjustment: Keep stock accurate.

Review the data model before loading opening stock.