Select only those records that have different/multiple values for a particular column

You could do something like:

select distinct x.id, x.lastname, x.firstname, x.email
from t as x
join (
    select id
    from t
    group by id
    having count(distinct email) > 1
) as y
    on x.id = y.Id    

select x.* 
from member as x
where x.id IN

    (
    select id
    from member
    group by id
    having count(distinct email) > 1
    )