我已经阅读了很多关于与此非常相似的问题的问题和答案,主要问题是他们使用 LIMIT
作为返回最新记录的解决方案,该记录不适用于此查询,因为我需要返回几个结果。
逻辑如下:
- 每条记录都有一个
effective_date
,当记录值生效时。 - 只拉回今天
effective_date
或已经通过的记录 - 在我拉回的记录中,根据该记录的"
date_entered
"给我最新的记录
到目前为止,我已经能够通过此查询完成除最后一点逻辑之外的所有逻辑。我不能在GROUP BY
后使用ORDER BY
,因为结果已经分组,所以我无法使用MAX()
日期。我需要在WHERE
语句中执行逻辑。
SELECT
aos_products.`name`,
cac_customize_agent_comp_cstm.commission_percentage_c,
cac_customize_agent_comp.date_entered
FROM
wn_writing_number
LEFT OUTER JOIN wn_writing_number_cac_customize_agent_comp_1_c ON wn_writing_number.id = wn_writing_number_cac_customize_agent_comp_1_c.wn_writing946b_number_ida
LEFT OUTER JOIN cac_customize_agent_comp_cstm ON wn_writing_number_cac_customize_agent_comp_1_c.wn_writing3148nt_comp_idb = cac_customize_agent_comp_cstm.id_c
LEFT OUTER JOIN cac_customize_agent_comp ON cac_customize_agent_comp_cstm.id_c = cac_customize_agent_comp.id
LEFT OUTER JOIN aos_products_cac_customize_agent_comp_1_c ON cac_customize_agent_comp_cstm.id_c = aos_products_cac_customize_agent_comp_1_c.aos_produca2b8nt_comp_idb
LEFT OUTER JOIN aos_products ON aos_products_cac_customize_agent_comp_1_c.aos_products_cac_customize_agent_comp_1aos_products_ida = aos_products.id
WHERE
wn_writing_number.id = 'b556d816-f2e6-b78f-c776-576c0542585c'
AND wn_writing_number_cac_customize_agent_comp_1_c.deleted = '0'
AND cac_customize_agent_comp_cstm.effective_date_c <= CURDATE()
GROUP BY aos_products.`name`
如果没有 GROUP BY,它将返回:
(varchar) (varchar) (datetime)
+---------+-------------------------+----------------------+
| name | commission_percentage_c | date_entered |
+---------+-------------------------+----------------------+
| Val 1 | 15.25 | 2016-07-06 23:57:28 |
+---------+-------------------------+----------------------+
| Val 1 | 15.75 | 2016-07-07 00:03:03 |
+---------+-------------------------+----------------------+
| Val 1 | 16 | 2016-07-07 00:31:08 |
+---------+-------------------------+----------------------+
| Val 2 | 14.75 | 2016-07-07 15:04:02 |
+---------+-------------------------+----------------------+
与组依据它返回
+---------+-------------------------+----------------------+
| name | commission_percentage_c | date_entered |
+---------+-------------------------+----------------------+
| Val 2 | 14.75 | 2016-07-07 15:04:02 |
+---------+-------------------------+----------------------+
| Val 1 | 15.25 | 2016-07-06 23:57:28 |
+---------+-------------------------+----------------------+
我想找回来的是:
+---------+-------------------------+----------------------+
| name | commission_percentage_c | date_entered |
+---------+-------------------------+----------------------+
| Val 2 | 14.75 | 2016-07-07 15:04:02 |
+---------+-------------------------+----------------------+
| Val 1 | 16 | 2016-07-07 00:31:08 |
+---------+-------------------------+----------------------+
因为我需要最新的 VAL 1 记录,例如
WHERE the datediff BETWEEN NOW() and date_entered = the smallest amount of time compared with other records
试试这个
SELECT *
FROM
(SELECT
aos_products.`name` as name,
cac_customize_agent_comp_cstm.commission_percentage_c as commission_percentage_c,
cac_customize_agent_comp.date_entered as date_entered
FROM
wn_writing_number
LEFT OUTER JOIN wn_writing_number_cac_customize_agent_comp_1_c ON wn_writing_number.id = wn_writing_number_cac_customize_agent_comp_1_c.wn_writing946b_number_ida
LEFT OUTER JOIN cac_customize_agent_comp_cstm ON wn_writing_number_cac_customize_agent_comp_1_c.wn_writing3148nt_comp_idb = cac_customize_agent_comp_cstm.id_c
LEFT OUTER JOIN cac_customize_agent_comp ON cac_customize_agent_comp_cstm.id_c = cac_customize_agent_comp.id
LEFT OUTER JOIN aos_products_cac_customize_agent_comp_1_c ON cac_customize_agent_comp_cstm.id_c = aos_products_cac_customize_agent_comp_1_c.aos_produca2b8nt_comp_idb
LEFT OUTER JOIN aos_products ON aos_products_cac_customize_agent_comp_1_c.aos_products_cac_customize_agent_comp_1aos_products_ida = aos_products.id
WHERE
wn_writing_number.id = 'b556d816-f2e6-b78f-c776-576c0542585c'
AND wn_writing_number_cac_customize_agent_comp_1_c.deleted = '0'
AND cac_customize_agent_comp_cstm.effective_date_c <= CURDATE()
ORDER BY cac_customize_agent_comp.date_entered DESC) t
GROUP BY t.name
这样做的想法是在使用group by
之前按date_entered
对记录进行排序。 从这篇文章中,groupby
将按照正常SELECT
的相同顺序选择第一个。
使用 max() 表示最新日期时间
SELECT
aos_products.`name`,
cac_customize_agent_comp_cstm.commission_percentage_c,
max(cac_customize_agent_comp.date_entered) as date_entered
FROM
wn_writing_number
LEFT OUTER JOIN wn_writing_number_cac_customize_agent_comp_1_c ON wn_writing_number.id = wn_writing_number_cac_customize_agent_comp_1_c.wn_writing946b_number_ida
LEFT OUTER JOIN cac_customize_agent_comp_cstm ON wn_writing_number_cac_customize_agent_comp_1_c.wn_writing3148nt_comp_idb = cac_customize_agent_comp_cstm.id_c
LEFT OUTER JOIN cac_customize_agent_comp ON cac_customize_agent_comp_cstm.id_c = cac_customize_agent_comp.id
LEFT OUTER JOIN aos_products_cac_customize_agent_comp_1_c ON cac_customize_agent_comp_cstm.id_c = aos_products_cac_customize_agent_comp_1_c.aos_produca2b8nt_comp_idb
LEFT OUTER JOIN aos_products ON aos_products_cac_customize_agent_comp_1_c.aos_products_cac_customize_agent_comp_1aos_products_ida = aos_products.id
WHERE
wn_writing_number.id = 'b556d816-f2e6-b78f-c776-576c0542585c'
AND wn_writing_number_cac_customize_agent_comp_1_c.deleted = '0'
AND cac_customize_agent_comp_cstm.effective_date_c <= CURDATE()
GROUP BY aos_products.`name`