I want to notify user when the service down and up and this is my design now (just for demo).
I would prefer to separate that becomes two records. And I would like to add Comment field that will explain about the problem why the services are down or how do you repair to restore the services.
The schema would be like
Table History HistoryID int, ServiceID int, Status varchar(4), StatusTime datetime2(3), Comment varchar(50)
Then, the Data would be like
HistoryID ServiceID Status StatusTime Comment 1 1 Down 2016-05-03 00:00:00 Problem happens because xxx 2 1 Up 2016-05-04 00:00:00 Restart the service
*EDIT if you want to show something like :
ServiceID: 1 donwtime:2016/05/03 uptime:2016/05/04.
you could use your schema to make the select statement easier. but I still recommend using Comment to let you know what cause the service down, and how can u fix it. It would make it better for maintaining your service. And you can insert a new row for each Down status, and update the last row for Up status. for example :
HistoryID ServiceID DownTime UpTime DownComment UpComment 1 1 xxx xxx xxx xxx 2 1 xxx NULL xxx NULL
first row means the service was already repaired and went UP at xxx time. second row means the service went down again, but hasnt been repaired.