hapus duplikat di postgre dan sql server

WITH tmp_tabel AS (
SELECT
        nilai1, test_id
        ROW_NUMBER() OVER (
            PARTITION BY
                    test_id
            ORDER BY
                    test_id
     ) row_num
     FROM
        test_null
        WHERE test_id ='1'
)
DELETE FROM tmp_tabel
WHERE row_num > 1;