Select single 优化

      READ TABLE LT_KONP INTO LS_KONP WITH KEY KNUMH  = LO_KNUMH .
      IF SY-SUBRC = 0.
        POUT_KBETR = LO_KBETR.
      ELSE.
        SELECT SINGLE KBETR
        FROM KONP
        WHERE KNUMH = @LO_KNUMH
        INTO @LO_KBETR.

        LS_KONP-KNUMH = LO_KNUMH.
        LS_KONP-KBETR = LO_KBETR.
        APPEND LS_KONP TO LT_KONP.
        CLEAR LS_KONP.

        POUT_KBETR = LO_KBETR.
      ENDIF.