VMS Help SCA, SCA Topics, Callable Routines, SCA$QUERY_SELECT_OCCURRENCE, Arguments  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 query_context
    type:       $SCA_QUERY_CONTEXT
    access:     read/write
    mechanism:  by reference

    An SCA query context that is to describe a specific entity.

 entity_handle
    type:       $SCA_HANDLE
    access:     read/write
    mechanism:  by reference

    An SCA entity handle that describes the entity that the newly
    defined query context is to match.