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Question

Александр

Asked:2020-06-13 23:59:21 +0000 UTC2020-06-13 23:59:21 +0000 UTC 2020-06-13 23:59:21 +0000 UTC

帮助复杂的sql查询

有一张表，有一个查询我想得到，比如2个值 -value的值之和和points的值之和，但我想不通如何同时为2个值做条件，可以吗？例如，值的总和：

`SELECT SUM(value) AS balance FROM db WHERE id>30 AND value>1000`;

积分也一样

`SELECT SUM(value) AS balance FROM db WHERE xxx=2 OR yyy=3`;

有什么办法可以将这两个查询合二为一吗？ SELECT SUM(value) AS balance, SUM(point) AS points FROM.... WHERE ??

所有这些前提是数据重叠并且不可能简单地将这两个条件连接到 WHERE

Denis · Answer 1 · 2020-06-14T00:03:50Z

Best Answer

Denis

是的你可以。将条件推where送到聚合函数中sum：

select id,
    sum(if(xxx = 2 or yyy = 3, value, 0)) as balance_1,
    sum(if(id > 30 AND value > 1000, value, 0)) as balance_2
from db
group by id

Darth · Answer 2 · 2020-06-14T00:04:11Z

Darth

可能有更优雅的解决方案，但您可以直接使用子查询-

SELECT 
     balance = (SELECT SUM(value) FROM db WHERE id>30 AND value>1000), 
     points = (SELECT SUM(value) FROM db WHERE xxx=2 OR yyy=3`);