Backups can be run concurrently with most other database operations. Exceptions are:
No metadata changes can occur while the Catalog Store is backed up
No commands that issue checkpoints or DBCC
Be aware, however, that transactions that have not committed when you start a backup are not backed up. If a system or media failure occurs during backup, you cannot restore uncommitted transactions.
Once a backup is started, you cannot execute a CHECKPOINT command.
