SQL语句（oracle）分组获取最新一条数据
SELECT * FROM (
SELECT ROW_NUMBER() OVER(PARTITION BY x ORDER BY y DESC) rn,t.*
FROM test1 t
) WHERE rn = 1;
SELECT * FROM (
SELECT ROW_NUMBER() OVER(PARTITION BY x ORDER BY y DESC) rn,t.*
FROM test1 t
) WHERE rn = 1;
