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求求！waiting online

求求！waiting online# Database - 数据库

c*o2004-07-26 07:07

1 楼

How to get the EmpName from the following table. The EmpName's departments are
('cs' AND 'math').
(TABLE emp)
======================
EmpName Department

s*c2004-07-26 07:07

2 楼

select distinct EmpName
from emp e1
where exists
(select *
from emp e2
where e2.EmpName = e1.EmpName and e2.Department = 'cs') and
exists
(select *
from emp e3
where e3.EmpName = e1.EmpName and e3.Department = 'math');
Are you in interview:-)

are

【在 c*o 的大作中提到】

: How to get the EmpName from the following table. The EmpName's departments are
: ('cs' AND 'math').
: (TABLE emp)
: ======================
: EmpName Department

c*o2004-07-26 07:07

3 楼

Thank you! Is there any other more efficient one?

k*e2004-07-26 07:07

4 楼

select distinct EmpName
from emp e1
where e1.Department = 'cs' and
exists
(select *
from emp e3
where e3.EmpName = e1.EmpName and e3.Department = 'math');

【在 c*o 的大作中提到】

: Thank you! Is there any other more efficient one?

s*o2004-07-26 07:07

5 楼

Select distinct EmpName
From emp e1
Where e1.Department = 'cs'
INTERSECT
Select distinct EmpName
From emp e2
Where e2.Department = 'math'

are

【在 c*o 的大作中提到】

: How to get the EmpName from the following table. The EmpName's departments are
: ('cs' AND 'math').
: (TABLE emp)
: ======================
: EmpName Department