Navigation:  Samples > SelectiveRelation Sample

This example creates a Selective relationship between 2 tables.

 

FUNCTION Start

LOCAL oEng                AS DaoDbEngine

LOCAL oDb                AS DaoDatabase

LOCAL oOrders        AS DaoQuery

LOCAL oDetails  AS DaoQuery

LOCAL oProducts AS DaoQuery

Set color TO w+/b

cls

// Open the database.

oEng        := DaoDbEngine{}

oDb        := oEng:OpenDatabase("\VO2jet\Northwind.mdb",NIL,NIL,NIL)

 

// Open a recordset on Orders table.

// and also a recordset on the OrderDetails table

oOrders := DaoQuery{"Orders",DbOpenDynaSet,DbReadOnly,oDb}

oDetails := DaoQuery{"Order Details",DbOpenDynaSet,DbReadOnly,oDb}

oProducts := DaoQuery{"Products",DbOpenDynaSet,DbReadOnly,oDb }

oOrders:SetRelation(oDetails, #OrderId                ,"OrderId")

oDetails:SetRelation(oProducts, #ProductId        , "ProductID")

DO WHILE ! oOrders:Eof .and. oOrders:Recno < 5

 ? "Order: ",oOrders:FIELDGET(#orderId), oOrders:FIELDGET(#OrderDate)

 DO WHILE ! oDetails:Eof

         //oProducts:FindFirst("ProductId = " + Ntrim(oDetails:Fieldget(#ProductId)))

         ? "Detail:",oDetails:FIELDGET(#OrderId), oDetails:FIELDGET(#ProductId), oProducts:FIELDGET(#Productname)

         oDetails:Skip(1)

 ENDDO

 oOrders:Skip(1)

ENDDO

 

oDb:Close()

wait