How to resolve ORA-00937: not a single-group group function when calculating percentage?

Question

I\'m trying to get a percentage of the itemid that are available in a certain area. Using my query, I get an error ORA-00937: not a single-group group function<

Answer 1

Use Group 'By clause':

Select department_id, min(salary)
From employees
Group By department_id
Having min(salary) >
(
    Select min(salary)
    From employees
    Where department_id <> 50
);