使用In命令和group by子句

Question

我正在尝试从两个表（部门和人员）中获取一些数据， 我的工作基本上是使用in子句。有人可以在以下查询中帮助我确定问题吗？

from email.department, email.person
where person.works_in in (select person.works_in from email.person
             having salary > avg(person.salary) group by (person.works_in));

ERROR:  syntax error at or near "group"
LINE 16:              having salary > avg(salary) group by (person.wo.

I am getting the above error

UPDATED: 
select person.works_in from email.person                    
group by person.salary,person.works_in
having salary > avg(salary);

the query is executed but, Now, I get nothing in the return value. 

Answer 1

也许我错了，但是在我看来，您想选择salary高于平均水平的人。您无需使用group by和having就可以实现它。我假设您的桌子上每人只有一行。

select works_in
from email.person
where salary > (select AVG(salary) from email.person)