Upgrade the database to SQL server 2008

if I need to upgrade the database of website that operates 24x7 from SQL Server 2005 to SQL Server 2008.

What the plan I need to task for the upgrade process with the minimum downtime possible ?

What are the steps required to upgrade the database ?

What do I need to check before the upgrade? Performance ? Logins ?

Someone told me that if I get another server it will the best to install SQL Server 2008 instance on and then backup the db and restore to the new server after that开发者_StackOverflow社区 change the name of new server to the real one and the application will work with no changes.

Is that true ??

The default instance name will also change if I change the name of the server?

I tend to agree with your "some 1"...the best way to do this would be to have a second server that you get the database up and running on, make sure your old connection string connects to it, and then switch over to it.

This sidesteps the whole issue of testing your application with the new version...there are differences in behavior in the 2008 query engine versus 2005 that can cause problems, particularly if you have really complicated stored procedures. You need to test it...there's no way around it.

Having said that, while I know that these differences exist academically, I've never had any problems moving to 2008 from 2005. Microsoft has a tool, Sql Upgrade Advisor, which might help you identify any problems moving forward.