With Telerik OpenAccess ORM you can set the connection string at runtime - here
you can find more information about how to do that.
Changing the connection string at runtime depends on the scenario you use and is generally not recommended. The new connection string has to be for a database with the same schema like your model. For working with multiple models, you can look here
If you have any questions or you need some clarifications regarding the approaches mentioned, do not hesitate to get back to us with more details about your scenario.
All the best,
the Telerik team
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