用于加入两个查询的MySQL查询

Question

我有一个mysql表，每行有一个学期的注册号，dob，学生姓名，性别，总分数。 我想在单个SQL查询中以总分数降序获得10个男孩和5个女孩的记录。

Answer 1

我的MySQL的方言是生锈的，但这应该做的伎俩

(SELECT * FROM Students WHERE sex = 'Male' ORDER BY TotalMarks DESC LIMIT 10) 
UNION ALL 
(SELECT * FROM Students WHERE sex = 'Female' ORDER BY TotalMarks DESC LIMIT 5) 

这是一个单一的查询，请注意。

Answer 2

试试这个代码：

select 
    a.studentID, 
    a.studentName, 
    a.dob, 
    a.totalMark 
from 
(
    select 
     studentID, 
     studentName, 
     dob, 
     totalMark 
    from 
     students 
    where 
     sex='M' 
    order by 
     studentMark desc 
    limit 10 
    union all 
    select 
     studentID, 
     studentName, 
     dob, 
     totalMark 
    from 
     students 
    where 
     sex='F' 
    order by 
     totalMark desc 
    limit 5 
) 
order by 
    totalMark desc 

Answer 3

试试这个

select * from 
    (select reg_number, dob, student_name, sex, total_marks where sex='male' 
    order by total_marks desc limit 10 
    union 
    select reg_number, dob, student_name, sex, total_marks where sex='female' 
    order by total_marks desc limit 5) a order by total_marks desc