I am attempting to add Entity Framework, code first, to an MVC application that's been running with test data, using the CTP4 preview.
I am currently getting this error:
The model backing the 'SchedulerContext' context has changed since the database was created. Either manually delete/update the database, or call Database.SetInitializer with an IDatabaseInitializer instance. For example, the RecreateDatabaseIfModelChanges strategy will automatically delete and recreate the database, and optionally seed it with new data.
I do not want to generate a database at all, as I already have a database. So I tried adding the following to the SchedulerContext constructor:
Database.SetInitializer<SchedulerContext>(new CreateDatabaseOnlyIfNotExists<SchedulerContext>());
which had no effect at all -- I got the same error the next time it ran. The error seems to occur when it is executing a LINQ statement that accesses the database -- the first, I think.
Where should I put this statement, or is this statement the answer to this problem at all?
I simply glossed over the fact you already have a database and don't want to create another one...in that case the answer is to put this in your SchedulerContext class
protected override void OnModelCreating(System.Data.Entity.ModelConfiguration.ModelBuilder modelBuilder) {
modelBuilder.IncludeMetadataInDatabase = false;
}
You usually put it in the Global.asax
protected void Application_Start() {
Database.SetInitializer<SchedulerContext>(new CreateDatabaseOnlyIfNotExists<SchedulerContext>());
}
Note that it will only be initialized on first use of the data context.
public class DataContextInitializer : CreateDatabaseOnlyIfNotExists<SchedulerContext> {
protected override void Seed(SchedulerContext context) {
}
}
Then you modify the SetInitializer like so.
System.Data.Entity.Infrastructure.Database.SetInitializer<SchedulerContext>(new DataContextInitializer());
Btw, as of CTP5, this is the proper way of setting the initializer in Global.asax
protected void Application_Start()
{
System.Data.Entity.Database.DbDatabase.SetInitializer<NerdDinners>(new System.Data.Entity.Database.DropCreateDatabaseIfModelChanges<NerdDinners>());
}
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