OpenSQL 与列之间的比较

Question

我可以在 OpenSQL 中比较 table 的列吗？

目前代码如下所示：

  SELECT SINGLE menge wemng ebeln ebelp
    INTO (eket-menge,
          eket-wemng,
          eket-ebeln,
          eket-ebelp)
    FROM eket
    WHERE ebeln = ekpo-ebeln
      AND ebelp = ekpo-ebelp.

  IF eket-menge NE eket-wemng.

我想避免检索 menge = wemng 处的行，但这不起作用：

  SELECT menge wemng ebeln ebelp
    INTO (eket-menge,
          eket-wemng,
          eket-ebeln,
          eket-ebelp)
    FROM eket
    WHERE ebeln = ekpo-ebeln
      AND ebelp = ekpo-ebelp
      AND menge <> wemng.

ABAP 认为 wemng 应该是一个变量。

我该怎么做？

Answer 1

请检查以下查询：

  SELECT menge wemng ebeln ebelp
  INTO (eket-menge,
        eket-wemng,
        eket-ebeln,
        eket-ebelp)
  FROM eket
  WHERE ebeln = ekpo-ebeln
    AND ebelp = ekpo-ebelp
    AND menge <> eket~wemng.

但是此时你得到错误：

Incorrect nesting: Before the statement "ENDIF", the control structure introduced by "SELECT" must be concluded with "ENDSELECT".

所以你应该创建一些内部 table 来处理这个

  SELECT menge wemng ebeln ebelp
  INTO TABLE lt_eket
  FROM eket
  WHERE ebeln = ekpo-ebeln
    AND ebelp = ekpo-ebelp
    AND menge <> eket~wemng.

或使用SELECT SINGLE

  SELECT SINGLE menge wemng ebeln ebelp
  INTO (eket-menge,
        eket-wemng,
        eket-ebeln,
        eket-ebelp)
  FROM eket
  WHERE ebeln = ekpo-ebeln
    AND ebelp = ekpo-ebelp
    AND menge <> eket~wemng.

Answer 2

在 WHERE 条件下比较两列时，您应该使用列选择器 (~)。这是设计使然。

ABAPDOCU 说：

Column selector

Character ~. A column (col) of a database table (dbtab) can be addressed in a SELECT statement by means of dbtab~col. This type of addressing is necessary when multiple database tables are accessed if the name of a column occurs in a number of different database tables or if two columns are compared with each other in a comparison in the WHERE condition.

所以，在你的情况下：

SELECT menge wemng ebeln ebelp
    INTO (eket-menge,
          eket-wemng,
          eket-ebeln,
          eket-ebelp)
    FROM eket
    WHERE ebeln = ekpo-ebeln
      AND ebelp = ekpo-ebelp
      AND menge <> eket~wemng.
...

OpenSQL 与列之间的比较

OpenSQL with comparison between columns

abap

opensql