如何在sql和php中填写最小值？

Question

我在 SQL 中有一个 table:

Table 1

date       name  s1   s2   s3   s4   min_value
7/10/2017  ram   10   11   12   13   11
7/10/2017  tom   17   16   15   14   16
7/10/2017  ara   13   9    26   22   9

如果我在一个日期内计算所有字段的总和，那么

s1 total value 40
s2 total value 36
s3 total value 53
s4 total value 49

这里minimum value是36，意思是minimum value列是s2.

我分别在min_value字段中插入了s2字段值

我的问题是how will I fill min_value field?

请帮帮我。

提前致谢。

Answer 1

实现代码如下：

SELECT [date], s1, s2, s3, s4,
    case when s1 < s2 and s1 < s3 and s1 < s4 then s1
         when s2 < s1 and s2 < s3 and s2 < s4 then s2
         when s3 < s1 and s3 < s2 and s3 < s4 then s3
         else s4 end as [min_value]
FROM (
    SELECT [date], sum(s1) AS s1, sum(s2) AS s2, sum(s3) AS s3, sum(s4) AS s4 FROM [Table1]
    GROUP BY [date]
) AS A

如何在sql和php中填写最小值？

How to fill min value in sql and php?

php

sql

min