Question

我无法做到这一点

+------------+------------+------------+
|   Name     | year       | Value      |
+------------+------------+------------+
| Name1      | 2015       |        100 |
| Name1      | 2014       |        150 |
| Name1      | 2013       |        200 |
| Name2      | 2015       |        130 |
| Name2      | 2014       |        160 |
| Name2      | 2013       |        220 |
+------------+------------+------------+

（2015年至2013年）的价值减去（2014年至2013年）的价值按名称分组

将输出

+------------+------------+
|   Name     | Value      |
+------------+------------+
| Name1      | 100        |
| Name2      | 130        |
+------------+------------+

或者无论如何我可以使用SUM和WHERE类似

(SUM(Name1 WHERE year <= "2014") - SUM(Name1 WHERE year <= "2015") ) AS Value
GROUP BY Name

Answer 1

你需要像这样的东西

 SELECT (SUM(IF(year <= 2015 AND year >= 2013,value,0) )
         - SUM(IF(year <= 2014 and year >= 2013,value,0) )) AS total_sum
FROM your_table_name
GROUP BY Name

这样就可以了解

Answer 2

你可以这样使用

 SELECT (SUM(IF(`year` <= 2015 and `year` >= 2013,value,0) ) ) as total_sum_2015 FROM `table`

2014年做同样的事情像这样

SELECT (
    SUM( IF( `year` <=2014
    AND `year` >=2013, value, 0 ) )
    ) AS total_sum_2014
    FROM `table`

PHP，MySQL如何在两个不同的日期范围内汇总数据

2 个答案: