What is included in a backup if database is still in use during processing? (4220555)

What is included in a backup file if the database is still in use during processing?

For example, if at 1pm, backup started, and a row has a value of 'X' at 1:15pm, the value changes to 'Y' at 3pm, then the backup completes at 4pm. If that backup file were restored, what value will be restored?

The process during the backup is:

1. The database is locked, blocking all transactions.
2. A mark is placed in the Transaction Log.
3. The database lock is released.
4. All the pages in the database are backed up.
5. The database is locked, blocking all transactions.
6. A mark is placed in the transaction log.
7. The database lock is released.
8. Extract all transactions between the two log marks and append to the backup.

This ensures that the backup file is completely consistent with the database at the time that the backup process completes. For the example described above, the answer would be 'Y', the backup file would restore the database to the state as of the time of the backup process's completion.

Applies to all versions of LiteSpeed and SQL Server 2000 and 2005