Remove duplicate records in a column

I published  some posts about dup records. But this is a beautiful logical query. Notice that it’s not optimized query.

delete T1
     from ( select id
                 , ROW_NUMBER() over ( order by id ) RowNum
                 from Tbl ) T1
        join ( select id
                    , ROW_NUMBER() over ( order by id ) RowNum
                    from Tbl ) T2 
           on T1.id = T2.id
           and T1.RowNum < T2.RowNum ;

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