The attributes on the left of γ go in GROUP BY. The aggregates on the right go in SELECT.

1. dept_name γ count(id) (instructor)
2. γ max(salary) (instructor)
3. dept_name γ sum(credits) as total_credits (course)
4. How many tuples does dept_name γ avg(salary) (instructor) return?
5. σ n > 1 (dept_name γ count(id) as n (instructor))