Do you mean that all transactions that get processed after starting the backup process won't get included in the backup?

>If you're using backup built into SQL Server, you don't need to worry about that because of how it handles transactions.
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>>Hello,
>>We have a backup function built in our c/s application that creates a backup file of one database, using SQL Server 2008 R2.
>>At this moment we do not check if another user is using the database and perhaps is doing updates, which could be a problem when doing a backup at the same time. It is possible to set the database to single user mode, but other users won't get notified and would be logged off. Is there a way to check if other users are logged on, and if no other user is logged on, then we could set the database to single user mode to prevent someone else to log on until the backup is finished.