SAP ABAP：如何獲取select某個條件下的條目數

       在ABAP中，有時候我們需要取某一條件下的條目數，要如何實現呢？

       這里有程咬金的三板斧：

（1）第一板斧：系統變量sy-dbcnt

  DATA: L_COUNT TYPE I.
  SELECT EQUI~EQUNR
         EQKT~EQKTX
         ILOA~SWERK
    INTO TABLE GT_EQUI
    FROM EQUI
    LEFT JOIN EQKT  ON  EQUI~EQUNR = EQKT~EQUNR  AND SPRAS = SY-LANGU
    LEFT JOIN EQUZ  ON  EQUI~EQUNR = EQUZ~EQUNR  AND EQUZ~DATBI = '99991231'
    INNER JOIN ILOA  ON  EQUZ~ILOAN = ILOA~ILOAN
    WHERE ILOA~SWERK IN S_SWERK
    AND   EQUI~ERDAT IN S_ERDAT .

  IF SY-SUBRC = 0.
    L_COUNT = SY-DBCNT.
  ENDIF.

（2）第二板斧：select  count （*）

  DATA: L_COUNT TYPE I.
  SELECT COUNT( * )
    INTO  L_COUNT
    FROM EQUI
    LEFT JOIN EQKT  ON  EQUI~EQUNR = EQKT~EQUNR  AND SPRAS = SY-LANGU
    LEFT JOIN EQUZ  ON  EQUI~EQUNR = EQUZ~EQUNR  AND EQUZ~DATBI = '99991231'
    INNER JOIN ILOA  ON  EQUZ~ILOAN = ILOA~ILOAN
    WHERE ILOA~SWERK IN S_SWERK
    AND   EQUI~ERDAT IN S_ERDAT .

  IF SY-SUBRC = 0.

  ENDIF.

（3）第三板斧：describe table  XXX  lines  XXX

  DATA: L_COUNT TYPE I.
  SELECT EQUI~EQUNR
         EQKT~EQKTX
         ILOA~SWERK
    INTO TABLE GT_EQUI
    FROM EQUI
    LEFT JOIN EQKT  ON  EQUI~EQUNR = EQKT~EQUNR  AND SPRAS = SY-LANGU
    LEFT JOIN EQUZ  ON  EQUI~EQUNR = EQUZ~EQUNR  AND EQUZ~DATBI = '99991231'
    INNER JOIN ILOA  ON  EQUZ~ILOAN = ILOA~ILOAN
    WHERE ILOA~SWERK IN S_SWERK
    AND   EQUI~ERDAT IN S_ERDAT .

  IF SY-SUBRC = 0.
*    L_COUNT = SY-DBCNT.
    DESCRIBE TABLE GT_EQUI LINES L_COUNT.
  ENDIF.