Question

I want design and implement an enterprise software with silverlight.I use sql server database for this.many useres run sql queireis on sql server database.
how can i configure sql server database for best performance?
how can i distribute sql server database for best performance?
how can i distribute sql server database between some servers for best performance?
and so what technologies can i use in sql server for best performance?

Answer 1

In addition to replication you can use mirroring or log shipping for this. Note that I am talking only about scaling out reads, not write. So reports etc. can be run from the copies of the database but writes must go to the main copy (unless you are using merge replication, which is frightening to me). There are some caveats of course.

With database mirroring, you can use the secondary as a read-only reporting source by taking a snapshot. There are limits here to how many databases you can mirror and there is of course maintenance to manage the snapshots. It is not quite true distribution of resources here, but it can be helpful to offload some of the load. In the next version of SQL Server (Denali), you will be able to set secondaries as read-only, so you can avoid the maintenance of snapshots.

With log shipping, you can essentially keep a stale version of the database around for reporting, and replace it periodically by restoring logs to it. You have a lot more flexibility here compared to replication or mirroring, as you can actually define a delay (like every 6 hours or once a day, you refresh the copy) – which can also serve as a “recover from a shoot-yourself-in-the-foot” scenario. The downside is that to restore a new copy of the database you need to kick all the current users out, as the database needs to be in single user mode in order to recover.

Those are just a couple of ideas for helping scale out reads, but deep down I agree with @gbn – are you solving a problem you don’t have yet? It’s one thing to design for scalability, but it’s very easy to step over that line and completely over-engineer.