从mysql表中的同一列获取计数?

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我想为不同的值计算相同的字段,例如:

user{user_id,gender}

性别可以有明显的男性或女性:)

我想得到所有男性和女性的数量,即

COUNT(male)   COUNT(female)  
   4               16

但我很困惑,因为他们来自同一性别coloumn谢谢

最佳答案
试试这个行的结果:

SELECT gender,COUNT(User_id) AS count
FROM User
GROUP BY gender;

输出

| gender | count |
|--------|-------|
|      F |     4 |
|      M |     2 |

尝试使用总计的行方式结果:

SELECT  (IFNull(gender,'Total')) AS gender,COUNT(User_id) AS Count
FROM User
GROUP BY gender
WITH rollup;

输出

| gender | Count |
|--------|-------|
|      F |     4 |
|      M |     2 |
|  Total |     6 |

尝试以列方式结果:

SELECT
  COUNT(CASE WHEN gender = 'M' THEN User_id END) AS males,COUNT(CASE WHEN gender = 'F' THEN User_id END) AS females,COUNT(*) AS Total
FROM User;

输出

| males | females | Total |
|-------|---------|-------|
|     2 |       4 |     6 |

See this SQLFiddle

原文链接:https://www.f2er.com/mysql/433769.html

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