Hello, While I was preparing for the mid-term exam, in one of the slides I found the statement: If SELECT list includes an aggregate function and there is no GROUP BY clause, SELECT list cannot reference a column out with an aggregate function. For example, the following is illegal: SELECT staffNo, COUNT(salary) FROM Staff; However, in the subsequent slides, I see these statements as examples of using the aggregate functions (couple of examples below): SELECT COUNT(*) AS myCount FROM PropertyForRent WHERE rent > 350; SELECT COUNT(staffNo) AS myCount, SUM(salary) AS mySum FROM Staff WHERE position = ‘Manager’; What I mean to say is that according to the first statement, aren't these examples illegal as well? They don't have the HAVING clause, but WHERE clauses instead. Thanks in advance!