mysql左外连接条件_mysql – 左外连接的MAX条件

----------

samples

----------

SamplesID

stylenumber

stylename

status

-----------

samples_details

-----------

Samples_Details_ID

SamplesID

CustomerName

date_out

date_returned

updated (timestamp)

status

------------

samples_pictures

------------

SamplesPicID

SamplesID

尝试编写一个查询,它给出了样本中的所有行,samples_pictures中的所有匹配项(如果有)以及来自samples_details的最新记录(如果有).所以两个左外连接,但只检索最近的记录.

什么不起作用：

SELECT samples.*

, samples_pictures.SamplesPicID

, CustomerName

, date_out

, date_returned

, updated

, samples_details.status as txn_status

FROM samples

LEFT OUTER JOIN

( SELECT Samples_Details_ID

, samples_details.status as txn_status

, MAX(updated) as MaxUpdated

FROM samples_details

GROUP BY Samples_Details_ID

) AS MaxTable

ON MaxTable.SamplesID = samples.SamplesID

LEFT OUTER JOIN samples_pictures

ON samples.SamplesID = samples_pictures.SamplesID

任何帮助将不胜感激！