Question

无法让它发挥作用......这是我到目前为止所得到的：

SELECT CardCode, (sum(DocRate) DocRate/DocRate.Length)
FROM OPCH
WHERE DocRate > 1
  AND DocStatus = 'O'
  AND DocDate >= '20140101'
GROUP BY CardCode

尝试获取DocRate的总和（每行不同）并将其除以行数（得到平均值）。

这不起作用。

Answer 1

很容易，找到解决方案。
使用AVG()。

我的代码：

SELECT CardCode,
       avg(DocRate) DocRate
FROM OPCH
WHERE DocRate > 1
  AND DocStatus = 'O'
  AND DocDate >= '20140101'
GROUP BY CardCode

Answer 2

尝试使用子查询。

SELECT CardCode, (DocRate/length)
FROM
  (SELECT CardCode,sum(DocRate) DocRate, sum (DocRate.Length) length
FROM OPCH
WHERE DocRate > 1
  AND DocStatus = 'O'
  AND DocDate >= '20140101'
GROUP BY CardCode) doc
GROUP BY CardCode

SQL总和除以结果数

2 个答案: