Why should you care?

ShopNest enterprise clients want purchase orders tied to inventory receipts — ERP schema connects PO, Supplier, and StockMovement.

See it live — copy this example

Paste into a .NET project with EF Core packages, then run with LocalDB/SQL Server (dotnet ef / dotnet run).

public class PurchaseOrder { public int Id { get; set; } public int SupplierId { get; set; } public string Status { get; set; } = "Open"; public ICollection<PurchaseLine> Lines { get; set; } = new List<PurchaseLine>(); }
public class PurchaseLine { public int Id { get; set; } public int PurchaseOrderId { get; set; } public int ProductId { get; set; } public int Qty { get; set; } }

var openPo = await db.PurchaseOrders
    .Include(p => p.Lines)
    .Where(p => p.Status == "Open")
    .FirstOrDefaultAsync(p => p.Id == poId);

What happened?

• PurchaseOrder aggregate contains Lines.
• Include loads lines for goods receipt posting.
• Status tracks PO lifecycle in procurement module.

Practice next

1. Split ERP modules by folder namespace in Domain project.
2. Use transactions when PO receipt updates StockItem quantities.
3. Avoid one DbContext with 200 entities — consider bounded contexts.
4. Post receipt: update StockItem and set PO Status Received in one transaction.
5. Report open PO value with Sum on Lines Qty * unit cost projection.

Remember

ERP links procurement to inventory. PurchaseOrder aggregate with Lines. Consider multiple DbContexts for large ERP.

ShopNest procurement module

Warehouse posts PO receipt via EF transaction updating StockItem and PurchaseOrder status.

Outcome: Finance and inventory modules stay synchronized without manual journals.