Question : migrating from sql express 2005 to sql server 2008

Greetings,

I have a win 2003 server that has two applications running on sql express 2005.  One of them is our primary application for our office.  Up until now this server has been pretty much dedicated to this application.

I need to add a new application to this server.  It is MS small business financial. It runs on sql server 2008.  My plan is to migrate the other two applications to this version of sql after it is installed.  The two applications in question are called Total FBO and Fortis.  One is a point of sale for the private side of an airport and the other is a document management system.

SQL server 2008 requires the "Tools for sql express 2005" to be removed as part of its install.  I have been told that following that, sql express 2005 will continue to run normally and our applications will continue to function.  

My question is, after the installation of sql 2008, what is the likelyhood of the other version still working and our current application still functioning?  In this case I assume the best practice is to migrate everything to sql 2008 but can both versions run side by side while this transition takes place?

Also, this server is a domain controller on our network. It is not our primary dc, in the sense of how we use it. However there is a recomendation to not install sql 2008 on a domain controller.  How will this effect our situation and should we demote this server from dc status.  This would leave us with only one domain controller.

Thanks for any advice.

Sky

Answer : migrating from sql express 2005 to sql server 2008

skykuhl

Yes this is all possible.

I have a PDC on which I installed SQL 2005 Express
for our AVG Anti Virus Database.

Last year, I installed SQL 2008 Express on the PDC
for a small Time Study Database/Program

( I know it's not recommended but our company
 does not like to spend a while lot on I.T.)

and did exactly what your being asked to do.

I unistalled the SQL 2005 Express Tools (Management Studio etc.)
and when the SQL 2008 Express was finished I just connected
 to the AVG database.

Now I can manage both through the SQL 2008 Express Management Studio.

Hope this helps.