我只想在表中记录的每个最新date_中获得适当的行。
这是我下面的示例数据。
| number | landing_id | percentage | date_recorded |
+---------------------+------------+--------------------+
| 1 | 1 | 19 |2018-10-02 21:42:22 |
| 2 | 1 | 44 |2018-10-09 15:43:32 |
| 3 | null | null | null |
| 4 | 3 | 22 |2018-10-13 15:43:56 |
| 5 | 3 | 54 |2018-10-16 18:44:03 |
| 6 | 3 | 33 |2018-10-18 20:33:24 |
| 7 | null | null | null |
| 8 | 5 | 13 |2018-10-15 19:43:49 |
+---------------------+------------+--------------------+
我的查询代码。
SELECT
t1.landing_id,
t1.id_number,
t2.percentage,
MAX(t2.date_recorded)
FROM fish_landing AS t1
LEFT OUTER JOIN percentage AS t2
ON t1.landing_id = t2.landing_id
AND t2.date_recorded < NOW()
GROUP BY t1.landing_id
这是上面查询代码的结果，该百分比列与最新的date_recorded不匹配。
| number | landing_id | percentage | date_recorded |
+----------+------------+------------+--------------------+
| 1 | 1 | 19 |2018-10-09 15:43:32 |
| 2 | null | null | null |
| 3 | 3 | 22 |2018-10-18 20:33:24 |
| 4 | null | null | null |
| 5 | 5 | 33 |2018-10-15 19:43:49 |
| 6 | null | null | null |
+----------+------------+------------+--------------------+
我要显示的输出数据表是下表，具有从最新date_recorded开始的适当列百分比。
| number | landing_id | percentage | date_recorded |
+----------+------------+------------+--------------------+
| 1 | 1 | 44 |2018-10-09 15:43:32 |
| 2 | null | null | null |
| 3 | 3 | 13 |2018-10-18 20:33:24 |
| 4 | null | null | null |
| 5 | 5 | 54 |2018-10-15 19:43:49 |
| 6 | null | null | null |
+----------+------------+------------+--------------------+
我希望有人可以帮助我解决我的问题。