DEFINE VARIABLE hDset AS HANDLE NO-UNDO.
DEFINE VARIABLE hRel  AS HANDLE NO-UNDO.
CREATE DATASET hDset.
hDset:SET-BUFFERS(BUFFER ttOrder:HANDLE, BUFFER ttOrderLine:HANDLE).
hRel = hDset:ADD-RELATION(BUFFER ttOrder:HANDLE, BUFFER ttOrderLine:HANDLE,
  "OrderNum,OrderNum"). 
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