Before we can start, the current user should be set up as a warehouse employee.

This can be done by creating a new record in the Warehouse Employee table (7301).

We will create a new location, ORANGE, with a bin of BIN1. The location uses the Bin Mandatory option, as shown in the following screenshot:

Bin Mandatory

In a new purchase order, we can now select this new Bin Code and post a receipt. The system now creates a new record in the Bin Content table, which enables us to see the created Warehouse Entries.

Whenever a Bin is used for the first time, Microsoft Dynamics NAV will create a Bin Content record. A Bin Content record is neither master data nor a ledger entry or document. It is a special kind of table in the philosophy of Microsoft Dynamics NAV.

The C/AL code for the Bin Content handling can be found in codeunit Whse. Jnl.-Register Line (7301). To see which Bins are used for an item at any moment, we can open the Bin Content from the Item Card, as shown in the following screenshot:

The warehouse entries can be displayed by clicking on the Quantity (Base) field.

All warehouse documents start with a record Warehouse Request table (5765). These records are created when a sales or purchase document is released.

The warehouse receipt or shipment can be created in the following three ways:

The first two options will create a new warehouse document for each sales or purchase document. The latter allows us to combine orders in one warehouse document.

Using only the warehouse receipt and shipment document is basically just adding one layer on top of the sales and purchase document. The posting routines Whse. Post Shipment (5763) and Whse. Post Receipt (5760), do not actually post something to the warehouse; they just write back the Bin code to the Sales Line and Purchase Line table. Technically, this uses the same C/AL code as level 1.

We can see how this is done by looking at the InitSourceDocumentLines function of, for example, Codeunit Whse. Post Receipt (5760):

InitSourceDocumentLines
WhseRcptLine2.COPY(WhseRcptLine);
WITH WhseRcptLine2 DO BEGIN
  CASE "Source Type" OF
    DATABASE::"Purchase Line":
      BEGIN
        PurchLine.SETRANGE("Document Type","Source Subtype");
        PurchLine.SETRANGE("Document No.","Source No.");
        IF PurchLine.FIND('-') THEN
          REPEAT
              ...
              IF PurchLine."Bin Code" <> "Bin Code" THEN BEGIN
                PurchLine."Bin Code" := "Bin Code";
                ModifyLine := TRUE;
              END;
              ...
            IF ModifyLine THEN
              PurchLine.MODIFY;

When the source tables are updated, the system creates a normal purchase receipt or sales shipment using codeunits sales-post (80) and Purch. Post (90).

The warehouse request record is exactly the same as in level 2, but instead of creating a warehouse receipt or shipment, the system directly creates a warehouse activity header and line.

The warehouse activity header and line table are the internal Microsoft Dynamics NAV warehouse documents. There are five types of warehouse activity documents, they are as follows:

When only using the Require Put-away and Require Pick option on a location, document types Invt. Put-Away and Invt. Pick are used. This will also make sure that the purchase order and sales order will be processed by starting codeunit sales-post (80) and Purch. Post (90).

Both level 2 and level 3 setup options are one-step warehouse implementations. When receiving an item, we must provide the storage bin where the item will be stored until it is sold. There is no additional step.

Using the warehouse receipt and shipment documents allows us to combine sales and purchase documents on one warehouse document. This cannot be done using direct Put-away and Pick. Using direct Put-away and Pick, we can split one sales line or purchase line into multiple bins. This cannot be done using warehouse receipt and shipment documents.

The reason for this is the way the warehouse entries are created. Level 2 uses the Bin field in the Item Journal Line to create the warehouse entries.

Using level 3, the warehouse entries are created using codeunit Whse.-Activity-Post (7324). The Bin code is not written back into the sales line or purchase line. This means we also cannot use the Bin code field in the purchase receipt and sales shipment documents.

When the whse. put-away request is processed using the warehouse worksheet, it will result in a warehouse activity header and line. In this context, the system will use the Put-away and pick document type that we discussed in the previous section about level 3.

Technically, the documents for level 3 and level 4 are equal, but there are the following two differences:

Let's start with defining zones and default bins. A zone is a group of bins. Usually, they are located near each other physically but more importantly, they share some properties.

For each zone, we need to specify if it is allowed to receive, ship, put-away, and pick. This is done in the Bin Type list.

When defining the bins, it is recommended to use a logical name such as R-01-001 for Receipt row one shelf one:

The default bins are set up in the Location Card on the Bin tab. These bins can always be changed on each document.

The bin calculation is done for the put-away documents using templates. This template defines the rules for finding the correct bin to store the items:

The find options are stored in the put-away template line table (7308); they are as follows:

The C/AL code that handles the bin calculation is located in codeunit create put-away (7313). Let's have a look:

Code()
IF Location."Directed Put-away and Pick" THEN BEGIN
  BinType.CreateBinTypeFilter(BinTypeFilter,2);
  REPEAT
    QtyToPutAwayBase := RemQtyToPutAwayBase;
    IF NOT (PutAwayTemplLine."Find Empty Bin" OR 
      PutAwayTemplLine."Find Floating Bin") OR
      PutAwayTemplLine."Find Fixed Bin" OR
      PutAwayTemplLine."Find Same Item" OR
      PutAwayTemplLine."Find Unit of Measure Match" OR
      PutAwayTemplLine."Find Bin w. Less than Min. Qty"
    THEN BEGIN
        //Calc Availability per Bin Content
        IF FindBinContent("Location Code","Item No.",
          "Variant Code",WarehouseClassCode) 
        THEN
          REPEAT
            ...
          UNTIL (BinContent.NEXT(-1) = 0) OR EverythingHandled
      END ELSE BEGIN

        //Calc Availability per Bin
        IF FindBin("Location Code",WarehouseClassCode) THEN
          REPEAT
            IF Bin.Code <> "Bin Code" THEN BEGIN
              ...
            END;
          UNTIL (Bin.NEXT(-1) = 0) OR EverythingHandled
      END
    UNTIL (PutAwayTemplLine.NEXT = 0) OR EverythingHandled;

For each record in the put-away template line table, the system will try to find a bin. This means that if the rules of the first template line fail, it will use the second template line and so forth.

The two options Find Empty Bin and Find Floating Bin eliminate using the others. If these are true, the system will call the FindBin function. For the other options, it will use the FindBinContent function.