php - 一个查询中的多个数学值

Question

我的一个查询出现问题。

SELECT
        CASE WHEN b.value IS NULL 
        THEN sum(d.value)
        ELSE sum(d.value) + sum(b.value)
        END AS sumaWydatkow

        FROM data d
        LEFT JOIN data_bills b 
        ON  d.id = b.data_id
        WHERE   d.type = 0

        UNION

        SELECT

        CASE WHEN b.value IS NULL 
        THEN sum(d.value)
        ELSE sum(d.value) + sum(b.value)
        END AS sumaPrzychodow

        FROM data d
        LEFT JOIN data_bills b 
        ON  d.id = b.data_id
        WHERE   d.type = 1

我想对两列求和，或者如果其中一列 (data_bills) 为空，则仅对一张表求和，并具有两种版本的列类型:0 和 1。

但现在是一列有两条记录。我想要两列，每列一列。 我想问是否可以通过一个查询来完成？

谢谢

Answer 1

尝试这个查询:

SELECT
      ( SELECT
        CASE WHEN b.value IS NULL 
        THEN sum(d.value)
        ELSE sum(d.value) + sum(b.value)
        END AS sumaWydatkow

        FROM data d
        LEFT JOIN data_bills b 
        ON  d.id = b.data_id
        WHERE   d.type = 0
       ) type0,

      ( SELECT
        CASE WHEN b.value IS NULL 
        THEN sum(d.value)
        ELSE sum(d.value) + sum(b.value)
        END AS sumaPrzychodow

        FROM data d
        LEFT JOIN data_bills b 
        ON  d.id = b.data_id
        WHERE   d.type = 1
      ) type1

演示 --> http://www.sqlfiddle.com/#!2/6ec52/2