Select where count of one field is greater than one

Question

I want to do something like this:

SELECT * 
  FROM db.table 
 WHERE COUNT(someField) > 1

How can I achieve this in MySql?

Answer 1

For me, Not having a group by just returned empty result. So i guess having a group by for the having statement is pretty important

Answer 2

You can also do this with a self-join:

SELECT t1.* FROM db.table t1
JOIN db.table t2 ON t1.someField = t2.someField AND t1.pk != t2.pk

Answer 3

SELECT username, numb from(
Select username, count(username) as numb from customers GROUP BY username ) as my_table
WHERE numb > 3