Log Explorer unlocks your SQL Server Transaction Logs
A must-have tool for the professional DBA.
Lumigent calls this application a "transaction analysis and data recovery
solution for Microsoft SQL Server." I call it an essential tool for the
SQL Server 7.0 or SQL Server 2000 DBA whose users make mistakes. As far
as I know, that would be *every* DBA out there.
SQL Server, of course, keeps track of everything that affects data in
a transaction log, which is periodically rolled over into backup files
(at least, if you're being a conscientious DBA it is). But SQL Server
itself provides you with no way to see what's in the transaction log.
If something goes wrong with your database, you can restore from a backup
-- but there's no way to see in advance what that restore will do to the
data. Enter Log Explorer.
The process is simplicity itself. You choose a server, a database, and
a transaction log (either live or backed up). Then you can view every
transaction in the log -- what happened, when it happened, who the user
was, and exactly what data changed, was added, or was deleted. But better
yet, you can do thing with these transactions. User accidentally deleted
a row? No problem; right-click, select Undo Transaction, and Log Explorer
will generate a SQL Script for you that re-inserts the deleted data. You
can run the script directly from Log Explorer or from other tools such
as Query Analyzer. You can also create "redo transaction" scripts -- useful
for transferring changes from one server to another. A script can reverse
or recreate a single transaction, everything in a log, or a filtered subset
of the logged transactions (and the filtering tools are pretty good, too).
Other nice touches include the ability to recover entire deleted tables
and a real-time transaction monitor mode. Another handy section lets you
analyze the user load on your server and see which tables had the heaviest
activity. All in all, I can't imagine trying to run a busy SQL Server
installation without having this tool available. When I think about all
the time that Log Explorer *could* have saved me in the past, I realize
it would have paid for itself multiple times over.
Mike Gunderloy, MCSE, MCSD, MCDBA, is a former MCP columnist and the author of numerous development books.