Question

假设我有一个schools表和一个students表。 students表已连接到schools表，其列为NAME和BIRTHDATE。

我需要所有学校，其中包含学生，他们被称为“ jim ”或“ mike “并且在同一天出生。

类似的东西：

select *
  from schools s
  join student st in st.schoolId = s.Id
  where (...)

Answer 1

你可以通过两次加入学生来实现这一目标

select  distinct s.*
from    schools s
join    student st1
on      st.schoolId = s.Id
join    student st2
on      st.schoolId = s.Id
where   st1.birthdate = st2.birthdate and
        st1.name = 'Jim' and
        st2.name = 'Mike'

Answer 2

您可以简单地使用条件聚合来查找schoolId个birthdate，其中join和IN（或使用select s.* from schools s join ( select distinct schoodId from student where name in ('jim', 'mike') group by schoodId, birthdate having count(distinct name) = 2 ) st on s.Id = st.schoodId;）的名称与学校表一起获取相关细节。

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Answer 3

你一直在寻找：

select s.*
from schools s
    cross apply (select birthdate, name from students st where st.schoolId = s.Id and st.name = 'Jim') studentJim
    cross apply (select birthdate, name from students st where st.schoolId = s.Id and st.name = 'Mike') studentMike
where studentJim.birthDate = studentMike.birthDate

Answer 4

可以通过生日使用表格相关内部的joi

select t1.id from ( 
    select s.id , st.name, st.birthdate
    from schools s
    join student st in st.schoolId = s.Id
    where st.name  = 'jim' 
) t1 
inner join ( 
    select s.id , st.name, st.birthdate
    from schools s
    join student st in st.schoolId = s.Id
    where st.name  = 'mike' 
) t2 on t1.birthdate = t2.birthdate

Answer 5

试试这个：

select * from schools
where schools.id IN (

(select 
    s1.schoolID
from 
   student s1 inner join student s2
   on 
      (s1.schoolID = s2.schoolID) --seem school
      AND (s1.birthdate = s2.birthdate) --seem birthdate
      AND ((s1.name like '% jim %') OR (s1.name like '% mike %'))) --name jim or mike
)

希望这有帮助！

Answer 6

另一种形式（我没有测试过）可能是：

SELECT * 
 FROM SCHOOLS S
 INNER JOIN (
             SELECT A.SCHOOL_ID 
             FROM STUDENT A
             INNER JOIN STUDENT B ON A.BIRTHDATE = B.BIRTHDATE  AND A.SCHOOL_ID= B.SCHOOL_ID
             WHERE A.NAME = 'JIM'
             AND B.NAME = 'MIKE'
            ) C ON S.ID = C.SCHOOL_ID

学生在校内查询

6 个答案: