SQL query, count and group by

This could also be accomplished by joining the table with itself,

SELECT DISTINCT t1.name
FROM    tbl t1
        INNER JOIN tbl t2
        ON      t1.name = t2.name
WHERE   t1.key         != t2.key;

select name from table group by name having count(name) > 1

Couldn't be simpler...

Select Name, Count(Name) As Count 
    From Table
    Group By Name
    Having Count(Name) > 1
    Order By Count(Name) Desc

This could also be extended to delete duplicates:

Delete From Table
Where Key In (
    Select Max(Key)
        From Table
        Group By Name
        Having Count(Name) > 1
    )

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