Question

这是一个有效的示例，但没有得到我需要的一切：

SELECT *, 
       SUM(price) AS total_revenue 
FROM payments 
GROUP BY DATE(timestamp)

这将获得总收入（加上price，但我还需要获得vendor = '22' AND credited = 'Vendor'处的总价格（就像我每天对价格所做的一样）。

这是我尝试过的：

SELECT *, 
       SUM(price) AS total_revenue, 
       (SELECT SUM(price) WHERE vendor = '22' AND credited = 'Vendor') AS vendor_revenue 
FROM payments 
GROUP BY DATE(timestamp)

我在做什么错或者有什么方法可以解决？

Answer 1

有条件的聚合是实现所需目标的最佳方法：

SELECT
    DATE(timestamp) AS ts,
    SUM(price) AS total_revenue,
    SUM(CASE WHEN vendor = '22' AND credited = 'Vendor' THEN price ELSE 0 END) AS vendor_revenue
FROM payments
GROUP BY DATE(timestamp);

Answer 2

您的原始查询格式不正确-您将select *与group by一起使用。

SELECT DATE(p.timestamp), SUM(price) AS total_revenue,
       SUM(CASE WHEN vendor = 22 AND credited = 'Vendor' THEN price ELSE 0 END) as vendor_22_price
FROM payments p
GROUP BY DATE(p.timestamp)

分组依据内的子查询？

2 个答案: