While the licensing details can be somewhat complicated, the retail price of ~$7k/core is published on Microsoft's site at https://www.microsoft.com/en-us/sql-server/sql-server-2016-p.... Oracle's pricing is harder to come by but is closer to $25k/core for the Enterprise edition on x86 CPUs. There are often lots of extras involved in Oracle licensing, too, so the total cost differential between the two is generally higher than the per-core license cost differential.