Question

如何使用sql以下面的格式获得输出？我可以使用case sum来完成它，但是我无法在同一行中获得唯一的用户数。

id   unique_users  male_count  female_count
101      3            1            2
201      1            0            1
.
.

Answer 1

select id, 
       count(distinct user) as unique_users,
       sum(case when gender = 'M' then 1 else 0 end) as male_count,
       sum(case when gender = 'F' then 1 else 0 end) as female_count
from your_table
group by id

Answer 2

替代方案计算不同的男性和女性。

SELECT
  ID, 
  COUNT(DISTINCT "USER") AS unique_users,
  COUNT(DISTINCT DECODE(gender,'M',"USER")) AS male_count,
  COUNT(DISTINCT DECODE(gender,'F',"USER")) AS female_count
FROM your_table
GROUP BY ID
ORDER BY ID;

同样但没有Oracle特定的DECODE功能。

SELECT
  ID, 
  COUNT(DISTINCT "USER") AS unique_users,
  COUNT(DISTINCT CASE gender WHEN 'M' THEN "USER" ELSE NULL END) AS male_count,
  COUNT(DISTINCT CASE gender WHEN 'F' THEN "USER" ELSE NULL END) AS female_count
FROM your_table
WHERE ID = 101
GROUP BY ID
ORDER BY ID;

我引用了“USER”，因为它在Oracle中具有特定含义。

得到最近的

2 个答案: