Aggregate function in SQL WHERE-Clause

Question

In a test at university there was a question; is it possible to use an aggregate function in the SQL WHERE clause.

I always thought this isn\'t possibl

Answer 1

HAVING is like WHERE with aggregate functions, or you could use a subquery.

select EmployeeId, sum(amount)
from Sales
group by Employee
having sum(amount) > 20000

Or

select EmployeeId, sum(amount)
from Sales
group by Employee
where EmployeeId in (
    select max(EmployeeId) from Employees)