NAV 4 DB and NAV 5 DB on same SQL Server

There are no technical problems, only license problems. If you do not have Per Database granule, you have only one license for all databases on the server. And because this license will be upgraded to v. 5, some functionalities from v. 4 can have problems. Solution is to add the Per Database license granule into the license and use two separate licenses for each DB (old v4 license before upgrade for v4 database - per database, and v5 license uploaded into Master database)

slmaluwa wrote:

By the way, what do you think about running the same as
Ver 5 on SQL Server 2005
and
Ver 4.0 SP3 on Navision DB Server
on the same hardware (server). Someone earlier at our place said there will be performance issue. But, with dual XEON processor server, can't we set the affinity to allocate processor resources?

Well, technically this should be possible, but regarding performance this cannot be really recommended. Sure, you could set SQL Server's "Affinity Mask", excluding Core 0 (this one will be used by the NAV server) and define the "Min./Max. Memory" settings, but this would actually limit the SQL Server, thus degarding its preformance - depending on the transaction volue you want to process.
E.g. if SQL just runs on "half of a Dual Core" you just could expect "slow motion" processing from it.

Further, SQL Server has specific requirements in setting up the disk-subsystem, thus it is crucial to store the native db on different volumes.

Hence, such a setup requires SUFFICIENT hardware resources! If you don't have that, then just temorary this might be OK, but be aware of the "harm" you might do to the SQL Server ...

Best regards,
Jörg