Question

How do I switch the database that my entity model is connected to at runtime?

If I have a training database and a production database, for example, how can I make my application switch between the two by changing a setting in the application.

Answer 1

Justin Pihony has the correct answer.
If you want to access both databases at the same time (switch back and forth) instead of changing config and restarting app…..then you have two settings one for Train and one for Prod then you do your context like so:

string training = ConfigurationManager.ConnectionStrings["Train"].ToString();
string production = ConfigurationManager.ConnectionStrings["Prod"].ToString();

.....
EFContext context = null;
if (InTraining) 
   context = new EfContext(training);
else
   context = new EfContext(production);