我需要一个SQL选择查询才能使用两个SQL Server表首先获取日志表数据,实际上我为什么使用日志表,因为当用户将更新他的文件时,它将存储在Table_AttachLog
中,但是我友好地使用两个表之间的内部连接,因为它是记录表。我知道使用DESC使用updateddate
列订单,我们可以获得如何使用两个表。
table_attachlog
RegistrationID uploaded File updateddate
---------------------------------------------------------------------
101 myprofile.doc 2018-03-25 00:45:08.500
table_registration
RegistrationID Name Email uploaded File submitted
----------------------------------------------------------------------------
100 Rohan rohan@gmail.com rohanfile.doc 2018-01-12 00:45:08.500
101 mazhar mazhar@gmail.com myprofile.doc 2018-03-13 00:45:08.500
102 raj raj@gmail.com raj.doc 2018-01-16 00:45:08.500
我需要查询,即table_attachlog的更新日期应通过desc进行一阶,请访问以下
RegistrationID Name Email uploaded File submitted
----------------------------------------------------------------------------
101 mazhar mazhar@gmail.com myprofile.doc 2018-03-13 00:45:08.500
100 Rohan rohan@gmail.com rohanfile.doc 2018-01-12 00:45:08.500
102 raj raj@gmail.com raj.doc 2018-01-16 00:45:08.500
左JOIN ISNULL应该这样做
select r.*
from Table_Registration r
left join Table_AttachLog a
on a.RegistrationID = r.RegistrationID
order by isnull(a.updateddate, r.submitted) desc