일반적으로 group by 또는 windows 함수를 이용해서 처리가 가능합니다만

지금 같은 경우는 sl_cd의 어떤 값을 써야 하는지가 정해져야 정확하게 답을 드리겠네요.

WITH TMP AS (
    SELECT '이수진' AS supy_nm, '710' as sl_cd from dual union all
    SELECT '이수진' AS supy_nm, '711' as sl_cd from dual 
)

select supy_nm, max(sl_cd) as sl_cd
  from tmp
 group by supy_nm
;


WITH TMP AS (
    SELECT '이수진' AS supy_nm, '710' as sl_cd from dual union all
    SELECT '이수진' AS supy_nm, '711' as sl_cd from dual 
)

select supy_nm, sl_cd
  from (
        select supy_nm, sl_cd, row_number() over (partition by supy_nm order by sl_cd desc) as rnum
        from tmp
        )
 where rnum = 1
;