GROUP BY clause and table join

This is probably simple but I’m just trying to learn SQL. I have two tables.

employee table;

department table;

I’m try to use GROUP BY and table join to get the department name “dname” and the COUNT of the employees in each department that has a COUNT of more than 3 employees. If I use:

SELECT dname, COUNT(employee.dno)

FROM employee

INNER JOIN department ON department.dnumber = employee.dno

WHERE COUNT(employee.dno)>3

GROUP BY dname;

I get: Invalid use of group function

Thanks for help.

why767