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如何使用MS-Access-2010 SQL将多个字段的最大值分配给select语句中的单列?
原标题:How to assign the max value across mulptiple fields to a single column in a select statement using MS-Access-2010 SQL?

我在一个表中有多个列,但我只希望在sql中选择列中的最高值。

示例信息:

D1     D2     D3     D4
-----  -----  -----  -----
3      2      150    5
1      3      20     10

输出需要:

MaxPower
150
20

有人知道这样做的好方法吗?一个单一的sql是可取的,但是vba也可以。

最佳回答
select max(v) as maggiore from (
select id,d1 as v from table
union all
select id,d2 from table
union all
select id,d3 from table
union all
select id,d4 from table
) as t
group by id
问题回答

从表中选择max(max(d1,d2),max(d3,d4))如何?





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