Release 10.1A: OpenEdge Development:
Progress 4GL Handbook

Defining a procedure to return Order Lines

This section discusses a procedure that retrieves the Order Lines from the database. This sample procedure is called h-fetchOlines.p. It takes the current Order Number as an INPUT parameter. It then defines a temp-table with the fields from the OrderLine table plus the Item Name and the total Weight for the quantity ordered. Finally, it defines an OUTPUT parameter to return the set of Order Lines as a temp-table to the caller:

/* h-fetchOlines.p -- retrieve all orderlines for an Order     and return them in a temp-table. */     DEFINE TEMP-TABLE ttOline LIKE OrderLine         FIELD ItemName LIKE ITEM.ItemName     FIELD TotalWeight AS DECIMAL LABEL "Tot.Wgt." .     DEFINE INPUT PARAMETER piOrderNum AS INTEGER     NO-UNDO.     DEFINE OUTPUT PARAMETER TABLE FOR ttOline.

Notice that you must define the temp-table before you use it in a parameter definition.

Using the INPUT parameter that passed in the Order Number, the code retrieves all the Order Lines for that Order. For each one, it creates a temp-table record.

The procedure then needs to move all the OrderLine fields from the database record into the temp-table. In addition, it must copy the Item Name from the Item table and a calculation of the total weight for the Order Line based on the weight of the item and the quantity ordered.

You could do this with a long ASSIGN statement that names and assigns each field, but there’s a shorter way to do this, using the BUFFER-COPY statement, as in this example:

FOR EACH OrderLine WHERE Orderline.OrderNum = piOrderNum,     ITEM OF OrderLine:         CREATE ttOline.         BUFFER-COPY OrderLine TO ttOline             ASSIGN ttOline.ItemName = Item.ItemName                 ttOline.TotalWeight = OrderLine.Qty * Item.Weight. END.