SQL Query To Obtain Value that Occurs more than once

Question

I need to query my database to show the records inside my table where lastname occurs more than three times. Example: in my Students Table, there are 3 people with Lastname

Answer 1

From Oracle (but works in most SQL DBs):

SELECT LASTNAME, COUNT(*)
FROM STUDENTS
GROUP BY LASTNAME
HAVING COUNT(*) >= 3

P.S. it's faster one, because you have no Select withing Select methods here