查询：

Question

我有以下查询，该查询按每个月对每个所有者进行不同的项目计数

查询：

SELECT owner, Month(date) AS month, Count(DISTINCT( item )) AS cnt
        FROM   table_name
        WHERE  impact < 3
               AND group IN ( 'Group1', 'Group2', 'Group3')
               AND date >= '2019-01-01'
               AND date <= '2019-05-02 23:59:59'
        GROUP  BY owner, month
        ORDER  BY owner, month;

这将为每个所有者每月产生不同项目的计数。我想要的是每个月累计每个所有者的不重复项目数。对于2月，我想要从1月到2月的每个所有者的不同项目计数。对于3月，我想要从1月到3月的每个所有者的不同项目计数，依此类推。有人可以帮忙吗？

Answer 1

如果我的理解正确，您希望根据商品首次出现在所有者的首次的累计计数。在MySQL 8+中，您可以使用窗口函数：

SELECT owner, Month(date) AS month,
       COUNT(*) as this_month_cnt,
       SUM(COUNT(*)) OVER (PARTITION BY owner ORDER BY MONTH(date)) as running_cnt
FROM  (SELECT t.owner, t.item, MIN(t.date) as date
       FROM table_name
       WHERE impact < 3 AND
             group IN ( 'Group1', 'Group2', 'Group3') AND
             date >= '2019-01-01' AND
             date < '2019-05-03'
       GROUP  BY owner, item
      ) t
GROUP BY owner, month
ORDER  BY owner, month;

通过累积分组计算不同项目的数量

查询：

1 个答案: