northwind-core.sql Primary Key Names

[guni77]

Hello,
I noticed that the Primary Keys from in sqlite/northwind_core.sql e.g. in the table Employee now read entityId instead of employeeId. I use the nothwind.sql in mysql with my students and was a little confused when we tested northwind_core.sql with sqlite and the Primary Keys hat different names.
Is there a specific reason they where renamed? Or would it be possible to have both versions available for each database system.