怎么取指定日期的最近一笔数据

--写一个timestamp的SELECT *  FROM temp WHERE id =       (SELECT ok_id          FROM (SELECT t.*,                       lag(id) over(ORDER BY login_time) prev_id,                       lead(id) over(ORDER BY login_time) next_id,                       CASE                         WHEN (scn_time - lag(scn_time) over(ORDER BY login_time)) -                              (lead(scn_time) over(ORDER BY login_time) - scn_time) < 0 THEN                          lag(id) over(ORDER BY login_time)                         ELSE                          lead(id) over(ORDER BY login_time)                       END ok_id                  FROM (SELECT id, NAME, login_time, timestamp_to_scn(login_time) scn_time FROM temp) t)         WHERE login_time = to_timestamp('2010/3/23 16:13:36.397000', 'yyyy/mm/dd hh24:mi:ss.ff'));