Greetings -

I have a table as following:

lastname first name PermNO
x a 1
y b 2
z c 3
x a 1
x a 2
Wach person should have a unique PermNo. However due to bad data entry and not having the field specified as an ID, there are some people with more than one permNo., even though each person should have only one permno. For example, lastname "x", firstname "a", should always have his permno as 1, it should not be 2. The data above shows what I mean.

What I need is a query to list me all lastname, first name who have two or more PermNOs.