最大record对应数据的取得

① row_number() over(PARTITION的用法

SELECT code,
       BIR_YMD
FROM(SELECT t.code,
            t.bir_ymd,
            t.name,
            row_number() over(PARTITION BY t.code ORDER BY t.bir_ymd DESC ) AS rn
    FROM table1 t)m
    WHERE m.rn = 1

 

②MAX的用法

SELECT b1.code,
       b1.bir_ymd,
       b1.name
FROM table b1,
(
    SELECT code,
           MAX(bir_ymd) AS bir_ymd,
    FROM table
    GROUP BY code
) b2
WHERE b1.code = b2.code
AND b1.bir_ymd = b2.bir_ymd