How to delete duplicate all record & kept one record in SQL ?

Method - 1:

set rowcount 1 
DELETE FROM EMPLOYEE WHERE EMPID IN ( 
SELECT EMPID FROM EMPLOYEE 
GROUP BY EMPID
HAVING COUNT(*)>1 
) 
set rowcount 0




Method - 2:

WITH cte AS (SELECT *,ROW_NUMBER() OVER(PARTITION BY EMPID ORDER BY EMPID)'RowRank'
    FROM EMPLOYEE)
DELETE FROM cte
WHERE RowRank > 1