【发布时间】:2018-10-21 06:08:23
【问题描述】:
我已经为此工作了大约两天,但似乎无法弄清楚,所以我希望得到一些帮助。
我有两张桌子:
mysql> select id, date, volume, symbol_id from control_quotedaily limit 5;
+-------+---- -------+----------+-----------+
| id | date | volume | symbol_id |
+-------+------------+----------+-----------+
| 13263 | 2017-11-02 | 7800191 | AXISBANK |
| 13264 | 2017-11-02 | 9303981 | SBIN |
| 13265 | 2017-11-02 | 8013536 | HDFCBANK |
| 13266 | 2017-11-03 | 9642624 | AXISBANK |
| 13267 | 2017-11-04 | 19642327 | AXISBANK |
+-------+------------+----------+-----------+
5 rows in set (0.00 sec)
14 rows in set (0.01 sec)
mysql> select * from control_oidaily
+-----------+------------+-------------+--------------+
| symbol_id | date | expiry_date | val_in_lakhs |
+-----------+------------+-------------+--------------+
| AXISBANK | 2017-11-02 | 2017-11-30 | 166881.8 |
| AXISBANK | 2017-11-02 | 2017-12-28 | 2676.84 |
| AXISBANK | 2017-11-02 | 2018-01-25 | 97.13 |
| HDFCBANK | 2017-11-02 | 2017-11-30 | 76351.11 |
| HDFCBANK | 2017-11-02 | 2017-12-28 | 1509.48 |
| HDFCBANK | 2017-11-02 | 2018-01-25 | 0 |
| SBIN | 2017-11-02 | 2017-11-30 | 88654.3 |
| SBIN | 2017-11-02 | 2017-12-28 | 1060.51 |
| SBIN | 2017-11-02 | 2018-01-25 | 0 |
| AXISBANK | 2017-11-03 | 2017-11-30 | 87640.06 |
+-----------+------------+-------------+--------------+
所以对于 control_quotedaily 表中的每个报价,这就是我想要的:
- control_oidaily 表中该报价的最接近到期日期
- 我想要那个 expiry_date 的 val_in_lakhs。
例如:对于日期 2017-11-02,最接近的到期日是 2017-11-30,我希望返回 val_in_lakhs (76351.11)。
这就是我正在尝试的:
select o.date, o.expiry_date as expiry_date, o.symbol_id, q.date, q.symbol_id, o.val_in_lakhs, q.tottrdval, q.volume, q.symbol_id
FROM control_oidaily o
JOIN ( select o.date, MIN(expiry_date) as expiry_date, symbol_id
FROM control_oidaily o
GROUP by o.date,o.symbol_id
ORDER BY o.date asc) as ed
ON ed.date = o.date
AND ed.symbol_id = o.symbol_id
AND ed.expiry_date = o.expiry_date
JOIN control_quotedaily q
ON q.date = ed.date
AND q.symbol_id = ed.symbol_id
这是我期待的输出:
+-------+------------+----------+-----------+--------------+--------------+
| id | date | volume | symbol_id | expiry_date | val_in_lakhs |
+-------+------------+----------+-----------+--------------+--------------+
| 13263 | 2017-11-02 | 7800191 | AXISBANK | 2017-11-30 | 166881.8 |
| 13264 | 2017-11-02 | 9303981 | SBIN | 2017-11-30 | 88654.3 |
| 13265 | 2017-11-02 | 8013536 | HDFCBANK | 2017-11-30 | 76351.11 |
| 13266 | 2017-11-03 | 9642624 | AXISBANK | 2017-11-30 | 87640.06 |
+-------+------------+----------+-----------+--------------+--------------+
【问题讨论】:
-
expiry_date 列是哪种数据类型??您提供的样本的实际结果是什么(2017-11-02,最近的到期时间是 2017-11-30???
-
什么版本的 MySQL? (重要,v8 现在可用)最接近是否意味着小于或等于?表
control_quotedaily是否包含expiry_date列? (你不显示它。) -
2017-11-30有3个到期日,为什么你会优先选择76351.11而不是另外两个?
-
expiry_date 的数据类型是日期时间。最接近的大于或等于
-
在没有顶部/限制的子查询中排序是 nop。 PS请通过帖子编辑澄清,而不是cmets。谷歌“stackexchange 通知”,了解如何让非发帖用户通知您发表了评论。
标签: mysql database relational-database self-join jointable