Why should you care?

Finance and warehouse must agree on item quantities and costs.

See it live — copy this example

Run in SQL Server Management Studio (SSMS) or Azure Data Studio.

USE DataVerse;
IF OBJECT_ID(N'dbo.Warehouses', N'U') IS NOT NULL DROP TABLE dbo.StockLevels;
IF OBJECT_ID(N'dbo.Warehouses', N'U') IS NOT NULL DROP TABLE dbo.Warehouses;
CREATE TABLE dbo.Warehouses (
    WarehouseId INT IDENTITY PRIMARY KEY,
    Code VARCHAR(10) NOT NULL UNIQUE,
    City NVARCHAR(50) NOT NULL
);
CREATE TABLE dbo.StockLevels (
    WarehouseId INT NOT NULL REFERENCES dbo.Warehouses(WarehouseId),
    ProductId INT NOT NULL REFERENCES dbo.Products(ProductId),
    Qty INT NOT NULL CHECK (Qty >= 0),
    CONSTRAINT PK_Stock PRIMARY KEY (WarehouseId, ProductId)
);
SELECT w.Code, p.Sku, s.Qty
FROM dbo.StockLevels s
JOIN dbo.Warehouses w ON w.WarehouseId = s.WarehouseId
JOIN dbo.Products p ON p.ProductId = s.ProductId;

What happened?

• StockLevels is a composite-key inventory balance per warehouse and product — classic ERP inventory.
• The SELECT is an on-hand report.

Practice next

1. Create Warehouses and StockLevels.
2. Seed one warehouse and two stock rows.
3. Update Qty inside a transaction when shipping.
4. Query warehouses with Qty = 0.
5. Add ReorderLevel and filter low stock.

Remember

ERP shares keys across modules. Inventory needs composite balances. Transactions protect stock movements.

Multi-warehouse ERP

DataVerse manufacturing tracks stock per warehouse.

Outcome: Transfers and shipments update one balance table.