MySQL : only_full_group_by multiple date isn't in group by

Question

当only_full_group_by激活时，正确的查询如何？

SELECT
    MAX(DATE (`date`)) AS `date_full`,
    WEEKDAY(`date`) AS `date_week`,
    COUNT(`id`) AS `visits`
    FROM `xxx_visits_stats` 
    WHERE YEAR(`date`) = YEAR("2017-01-01") 
    GROUP BY `date_week`
    ORDER BY `date` DESC

没有(禁用)only_full_group_by 它可以工作!

Answer 1

我认为您的问题是由于您按 GROUP BY 中未提及的列进行排序，而且也不是聚合。

试试这个:

  SELECT MAX(DATE(`date`)) AS `date_full`,
         WEEKDAY(`date`) AS `date_week`,
         COUNT(`id`) AS `visits`
    FROM `xxx_visits_stats` 
   WHERE YEAR(`date`) = YEAR("2017-01-01") 
   GROUP BY WEEKDAY(`date`)
   ORDER BY 1 DESC

这种形式的 ORDER BY 表示使用 SELECT 子句中的第一列进行排序。