Currently we're using SQL Server 2005. We're looking to upgrade to SQL Server 2012, but the biggest issue is the licensing cost and how to estimate it. As I understand it, you can purchase CALS or license by core. Licensing by cores is, I believe much more expensive than we need, because we don't have that many users. At most I estimate we could have as many as 50 simultaneous users, but likely that will be smaller than that. The machine we're going to be putting this onto (actually, a VM) is a 4 core machine, so licensing cores is way more expensive, than licensing by users/devices, given our scenario.
However, that still gets me back to asking how many users do we have using the system at once? How can I estimate that with our current SQL Server 2005 database?
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