Gar,

>In the documentation on transaction log backups, it looks like using a transaction log is straightforward when combined with a database backup.That is first you restore the database (full or full+differetial) then apply the transaction log backup. (If this is not as easy as it sounds please comment).

>But what I don't see anything on is how you can use the transaction log to undo a single transaction which has been committed. Suppose, for example someone did an update with no where clause - wiping out a column of data? A transaction log for that update exists. How do we use the transaction log to get the data back for that column?

If you know the time that the update was committed, you can restore the final transaction log up to a point in time using the STOP AT clause.

Hope this helps

Cheers
Steve Lea