You can enable/disable the 2nd Level Cache also in the Visual Designer. See the link for details.
The method you are trying to do, by disabling all by default and enabling the cache selectively for some domain classes, is not supported by Telerik OpenAccess ORM.
Instead, we are following the approach, that you have to decide to use the 2nd Level Cache and then get the opportunity to selectively not cache data of several domain classes. See this link for details on how to configure your caching strategy for your domain classes.
I hope this information is useful for you. Feel free to ask if you have any other question.
the Telerik team
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