database - MS Access：单个查询中的平均和总计算

Answer 1

您有单独的查询来计算10DayTotalVolume和10DayAvgVolume。我怀疑您可以在一个查询qry10DayVolumes中计算两者。

SELECT
    b.SYMBOL,
    Sum(b.VOLUME) AS 10DayTotalVolume,
    Avg(b.VOLUME) AS 10DayAvgVolume
FROM
    [tbl-B] AS b INNER JOIN
    qryLast10DaysStored AS q
    ON b.TIMESTAMP = q.TIMESTAMP
GROUP BY b.SYMBOL;

然而，这让我想知道10DayAvgVolume除了10DayTotalVolume / 10

类似的考虑适用于 15 天和 30 天的值。

最终，我认为你想要一些基于这样的起点的东西：

SELECT
    q10.SYMBOL,
    q10.[10DayTotalVolume],
    q10.[10DayAvgVolume],
    q15.[15DayTotalVolume],
    q15.[15DayAvgVolume],
    q30.[30DayTotalVolume],
    q30.[30DayAvgVolume]
FROM
    (qry10DayVolumes AS q10
    INNER JOIN qry15DayVolumes AS q15
    ON q10.SYMBOL = q15.SYMBOL)
    INNER JOIN qry30DayVolumes AS q30
    ON q10.SYMBOL = q30.SYMBOL;

这假设您已经创建qry15DayVolumes并qry30DayVolumes遵循我建议的方法qry10DayVolumes。

如果您想减少查询的数量，您可以为每个已qry??DayVolumes保存的查询使用子查询，但首先尝试这种方式以确保逻辑正确。

在上面的第二个查询中，由于字段名称以数字开头，可能会出现问题。将这些名称括在方括号中或将它们重新命名为qry10DayVolumes, qry15DayVolumes, 并qry30DayVolumes使用以字母而不是数字开头的别名。

我使用您上传的“ 2nd Upload.mdb ”测试了上面编写的查询，它从 Access 2007 运行时没有出现错误。这是该查询结果集的第一行：

SYMBOL 10DayTotalVolume 10DayAvgVolume 15DayTotalVolume 15DayAvgVolume   30DayTotalVolume 30DayAvgVolume
ACC-1             42909         4290.9            54892 3659.46666666667            89669 2988.96666666667

Answer 2

Access 不支持最高级的 SQL 语法和子句，所以这有点小技巧，但它可以工作，并且在您的小样本上速度很快。您基本上正在运行 3 个查询，但 Union 子句允许您合并为一个：

select
   Symbol,
   sum([10DayTotalVol]) as 10DayTotalV,
   sum([10DayAvgVol]) as 10DayAvgV,
   sum([15DayTotalVol]) as 15DayTotalV,
   sum([15DayAvgVol]) as 15DayAvgV,
   sum([30DayTotalVol]) as 30DayTotalV,
   sum([30DayAvgVol]) as 30DayAvgV

from (

      select
        Symbol, 
        sum(volume) as 10DayTotalVol, avg(volume) as 10DayAvgVol,
        0 as 15DayTotalVol, 0 as 15DayAvgVol,
        0 as 30DayTotalVol, 0 as 30DayAvgVol
      from
         [tbl-b]
      where
         timestamp >= (select min(ts) from (select distinct top 10 timestamp as ts from [tbl-b] order by timestamp desc ))
      group by
         Symbol   

      UNION

      select
        Symbol, 
        0, 0,
        sum(volume), avg(volume),
        0, 0
      from
         [tbl-b]
      where
         timestamp >= (select min(ts) from (select distinct top 15 timestamp as ts from [tbl-b] order by timestamp desc ))
      group by
         Symbol    

      UNION

      select
        Symbol, 
        0, 0,
        0, 0,
        sum(volume), avg(volume)
      from
         [tbl-b]
      where
         timestamp >= (select min(ts) from (select distinct top 30 timestamp as ts from [tbl-b] order by timestamp desc ))
      group by
         Symbol 
      ) s

group by 
   Symbol