Remove duplicate records except the first record in SQL

Question

I want to remove all duplicate records except the first one.

Like :

NAME
R
R
rajesh
YOGESH
YOGESH

Now in the above I want to remove the second "R" and the second "YOGESH".

I have only one column whose name is "NAME".

Answer 1

Use a CTE (I have several of these in production).

;WITH duplicateRemoval as (
    SELECT 
        [name]
        ,ROW_NUMBER() OVER(PARTITION BY [name] ORDER BY [name]) ranked
    from #myTable
    ORDER BY name
)
DELETE
FROM duplicateRemoval
WHERE ranked > 1;

Explanation: The CTE will grab all of your records and apply a row number for each unique entry. Each additional entry will get an incrementing number. Replace the DELETE with a SELECT * in order to see what it does.