setRel()
 Set a relation in the parent file
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 Prototype

     ERRCODE setRel(
                       AREAP wa,
                       LPDBRELINFO lpdbRelInfo
                     )

 Arguments

     wa is a pointer to self.

     lpdbRelInfo is a pointer to a structure containing information on a
     relation.

 Description

     setRel() adds lpdbRelInfo to the wa->lpdbRelations list.

 Default Behavior

     Sets a relation--as defined by lpdbRelInfo--in the parent file wa.  A
     copy of the lpdbRelInfo structure is placed in the wa->lpdbRelations
     list.

     setRel() notifies the child of its additional parent by calling
     childStart().

     Warning!  The lpdbRelInfo->lpaParent pointer must be the same as
     the work area pointer that is passed as the first argument.

 Implementation Notes

     .  If you replace this method in your RDD, locate the end of the
        wa->lpdbRelations chain and mark the lpdbriNext element to point to
        your new relation.

 Files  Header file is Rdd.api.