June 13, 2002 at 3:53 pm
Hello everyone, I have the following question:
I understand the difference between restore and recovery. Restore is the process of rolling forward (in the data files) all of the transactions in the transaction log that have been committed. Recovery is the process of rolling back (in the data files) all of the transactions in the transaction log that have not been committed. What I don't understand is, when and why does SQL Server write uncommited data to the data files? Thanks for your help.
June 13, 2002 at 4:18 pm
The order is:
1. write the changes to the log
2. Write the changes to the data
if the server shuts down between 1 and 2, then
a. commited transactions (as marked in the log) are written to the data. This is forward.
b. uncommitted transactions are not written and are removed from teh log. rollback.
Steve Jones
June 13, 2002 at 7:41 pm
Or more so, the data is roll forward from the TL to data when the process is completed or a COMMIT is issued.
"Don't roll your eyes at me. I will tape them in place." (Teacher on Boston Public)
Viewing 3 posts - 1 through 2 (of 2 total)
You must be logged in to reply to this topic. Login to reply