Question

使用oracle，如何使用单个查询执行此操作？

VALUE       TYPE        IDentifier     
12           aa         123
123          bb         123
323          aa         1234
1212         cc         123
2            aa         12345
123          dd         123

SELECT IDentifier , SUM(VALUE) AS typeAASum WHERE TYPE = 'aa'
SELECT IDentifier , SUM(VALUE) AS typeBBSum WHERE TYPE = 'bb'
SELECT IDentifier , SUM(VALUE) AS typeCCSum WHERE TYPE = 'cc'

所以我的结果将再次出现在一个查询中

   IDentifier     TypeAASum    TypeBBSum     TypeCCSum

重要的是我每个标识符只能获得一行。

Answer 1

SELECT Identifier,
        SUM(CASE WHEN TYPE = 'aa' THEN VALUE ELSE 0 END) AS typeAASum,
        SUM(CASE WHEN TYPE = 'bb' THEN VALUE ELSE 0 END) AS typeBBSum,
        SUM(CASE WHEN TYPE = 'cc' THEN VALUE ELSE 0 END) AS typeCCSum
FROM YourTable
GROUP BY Identifier

从哪里选择

1 个答案: