子查询作为列：嵌套子查询

Question

我有两个表'学生'和'团队'。我想根据球队名称显示学生人数，球队Team_id是主键。

我想这样

(SELECT(SELECT team,count(*) as team 
      FROM student GROUP BY team) AS total, 
    (SELECT team_name 
      from team WHERE team_id IN (SELECT team 
       FROM student GROUP BY team)) as team) 

我想输出

Team Name  Total Student 
----------------------------- 
Team 1   25 
Team 2   10 

表 '学生'

CREATE TABLE IF NOT EXISTS `student` (
    `id` int(255) NOT NULL AUTO_INCREMENT, 
    `rid` varchar(200) NOT NULL, 
    `sid` varchar(200) NOT NULL, 
    `name` varchar(600) NOT NULL, 
    `age` varchar(200) NOT NULL, 
    `dob` varchar(200) NOT NULL, 
    `sex` varchar(200) NOT NULL, 
    `weight` varchar(200) NOT NULL, 
    `height` varchar(200) NOT NULL, 
    `team` varchar(600) NOT NULL, 
    `age_group` varchar(200) NOT NULL, 
    `weight_group` varchar(500) NOT NULL, 
    `belt` varchar(200) NOT NULL, 
    `black_belt` varchar(200) NOT NULL, 
    `ikata` varchar(20) NOT NULL, 
    `ikumite` varchar(20) NOT NULL, 
    `team_kata` varchar(20) NOT NULL, 
    `special_entry` varchar(20) NOT NULL, 
    `challange` varchar(50) NOT NULL, 
    `state` varchar(200) NOT NULL, 
    `weapon` varchar(200) NOT NULL, 
    PRIMARY KEY (`id`) 
) ENGINE=MyISAM AUTO_INCREMENT=6 DEFAULT CHARSET=latin1; 

表 '团队'

CREATE TABLE IF NOT EXISTS `team` (
    `id` int(20) NOT NULL AUTO_INCREMENT, 
    `team_id` varchar(500) NOT NULL, 
    `team_name` varchar(500) NOT NULL, 
    `address` varchar(500) NOT NULL, 
    `coach_name` varchar(500) NOT NULL, 
    `coach_number` varchar(500) NOT NULL, 
    `coach_email` varchar(500) NOT NULL, 
    `gold` varchar(200) NOT NULL, 
    `state` varchar(500) NOT NULL, 
    PRIMARY KEY (`id`) 
) ENGINE=MyISAM AUTO_INCREMENT=4 DEFAULT CHARSET=latin1; 

Answer 1

好像你正在寻找这个

select a.team_name, count(*) 
from team as a 
inner join student as b on a.id = b.team 
group by a.team_name 

（使用适当的列加入）