If you have an application wide context( which is not the recommended scenario) then it is possible to avoid the extra load because the object was loaded and is saved with the same context. Be sure to be in the same transaction, meaning between loading and saving the object there is no other call to SaveChanges() in the context.
In general, Telerik OpenAccess ORM is optimized to do a less queries as possible. Therefore if an object is in either the first level or the second level cache, then there is no extra query call to the database.
To see the different approaches how to work with data in Telerik OpenAccess ORM, I would like to recommend our SDK where you can find various examples to have a good starting point.
To your question regarding performance measuring. This is always dependent on the data model and the way you work with your data. It is not easy to have reliable results here.
I hope this information is helpful for you.
Feel free to ask if you have any other question.
the Telerik team
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