Just got back from SoCal SQL 2005 Roadshow and User Group
I just got back from a whirlwind tour of SoCal. For thos of you who attended, drop me a line. I'd love to hear your feedback on the roadshow event or the user group meeting.
I always learn a lot when I come back from these types of events. We did the ask the experts at the end of the day and there were a ton of questions. The interesting thing was that the questions bubbled up mostly into SSIS and Database Mirroring questions. I'm going to try to answer some here since I think a lot of folks may have the same questions.
I also found a lot of people excited about SQL Server 2005. Anyway, here goes some of the Q&A we got:
DB Mirroring Question Sampler:
Q) What happens to open transactions in DB Mirroring on a failover?
A) It depends on the state of the transaction but we will always make sure the database comes up in a consistent state. That means that if the transaction has not been committed, we will roll it back.
Q) What does the witness server really do? Do I have to license it?
A) A witness is not required and it does no transaction processing or anything like that. It is there to allow automatic failover by providing quorum when the principal or mirror goes down. In our licensing, we have allowed even SQL Server Express which is free to act as a witness. Now, you can make a witness do other things so you will want to get a license besides Express if you are going to perform more capabilities than just witness capabilities.
Q) What's the performance overhead?
A) As with all performance questions, it depends. However, if safety is on, you will slow down the principal while it waits for acknowledgements from the mirror. Therefore, for highest performance, you can turn safety off but you lose some HA. Plus, in our Standard Edition, safety is always on. You can only turn safety off in the Enteprise Edition.
SSIS Question Sampler:
Q) How do I move to SSIS?
A) It's a migration. We have a migration wizard that will take your DTS packages and migrate them to SSIS. The thing you have to remember is that SSIS is not a minor upgrade to DTS. It's a re-write to make SSIS super scalable and have great performance and functionality. The good thing is that we still ship the DTS 2000 runtime in certain versions of SQL Server 2005 so you can continue to run your DTS packages even as part of a SSIS workflow.
Q) What's new in SSIS?
A) That's hard to answer is a few words but here's my shot at it. Rewritten code base and designer to make your enterprise ETL needs a reality at very low cost. Integration with a very large set of traditional (relational) and new datasources such as web services and XML. Advanced functionality such as text mining, data cleansing and rich debugging. Lots and lots more even beyond this.
Enjoy!
Tom