mysql - 过去 7 天的返回计数，已填写缺失日期

Question

我非常努力地生成过去 7 天内每一天的总销售额数据集，并填补缺失的天数。

对于我的示例数据，我正在寻找的结果是:

2019-01-05  0
2019-01-06  0
2019-01-07  0
2019-01-08  0
2019-01-09  0
2019-01-10  1
2019-01-11  0

我得到的是:

2019-01-05  0
2019-01-06  0
2019-01-07  0
2019-01-08  0
2019-01-09  0
2019-01-10  0
2019-01-11  0

示例数据，尽管为 SO 缩短了，看起来像这样，只有一行:

id | saleID            | amount      | created
---|-------------------|-------------|-------------
1  | 6032b317-1533.... | 20000       | 2019-01-10 23:56:4

ID = INT 11 Auto
saleID = CHAR 36 INDEX
amount = INT 11 INDEX
created = DATETIME INDEX

我的查询现在看起来像这样:

SELECT
    qb.dy AS saleDay,
    COALESCE(COUNT(ets.saleID), 0) AS saleDayTotal
FROM eventTicketSales AS ets 
RIGHT JOIN (
    SELECT curdate() AS dy UNION
    SELECT DATE_SUB(curdate(), INTERVAL 1 DAY) AS dy UNION
    SELECT DATE_SUB(curdate(), INTERVAL 2 DAY) AS dy UNION
    SELECT DATE_SUB(curdate(), INTERVAL 3 DAY) AS dy UNION
    SELECT DATE_SUB(curdate(), INTERVAL 4 DAY) AS dy UNION
    SELECT DATE_SUB(curdate(), INTERVAL 5 DAY) AS dy UNION
    SELECT DATE_SUB(curdate(), INTERVAL 6 DAY) AS dy        
) AS qb ON ets.created = qb.dy AND ets.created > DATE_SUB(curdate(), INTERVAL 7 DAY)
GROUP BY qb.dy
ORDER BY qb.dy ASC;

您可以 play with a fiddle here .

请告诉我我做错了什么，并建议如何解决。

谢谢。

Answer 1

... AS qb ON ets.created = qb.dy

您正在将日期时间与没有时间的日期进行比较。这不匹配，因为时间显然不相同。

要解决这个问题，您可以在比较之前将日期时间转换为日期，使用 DATE 函数:

... AS qb ON DATE(ets.created) = qb.dy