Where is modelBuilder.IncludeMetadataInDatabase in EF CTP5

entity-framework-4

With CTP4, I used to be able to do the following (as suggested by ptrandem):

modelBuilder.IncludeMetadataInDatabase = false

With this line of code, EF doesn't create the EdmMetadata table in my database, and doesn't track model changes.

I was unable to find a way to accomplish this in the new CTP5, so now every time I change my model, I get this:

The model backing the 'MyContext'
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
DropCreateDatabaseIfModelChanges
strategy will automatically delete and
recreate the database, and optionally
seed it with new data.

So, does everybody know where is the IncludeMetadataInDatabase property in CTP5? Thanks.

Best Answer

CTP5 includes a very cool feature called Pluggable Conventions that can be used to Add/Remove conventions. IncludeMetadataInDatabase has been removed and being replaced with a
pluggable convention that does the same thing for you:

modelBuilder.Conventions
            .Remove<System.Data.Entity.Database.IncludeMetadataConvention>();

Related Solutions

.net – Entity Framework 4 – Handling very large (1000+ tables) data models

The number I heard in a Microsoft screencast is a maximum of roughly 250 tables per EF model. That doesn't mean EF can't handle more - it might just be sensible to break up your 1000+ tables into several logical groups of tables, and use one EF model per such logical group (with up to 250 tables in it).

I highly doubt you'll have queries that will need to use all 1000 tables at once - most likely not even 10 at once. So you should definitely be able to split up your pretty large model into smaller clusters and turn each into a separate EF model.

C# – Entity Framework Code Only error: the model backing the context has changed since the database was created

I found the answer in the comments on this post on Scott Guthrie's blog.

http://weblogs.asp.net/scottgu/archive/2010/08/03/using-ef-code-first-with-an-existing-database.aspx

For those who are seeing this exception:

"The model backing the 'Production' context has changed since the database was created. Either manually delete/update the database, or call Database.SetInitializer with an IDatabaseInitializer instance."

Here is what is going on and what to do about it:

When a model is first created, we run a DatabaseInitializer to do things like create the database if it's not there or add seed data. The default DatabaseInitializer tries to compare the database schema needed to use the model with a hash of the schema stored in an EdmMetadata table that is created with a database (when Code First is the one creating the database). Existing databases won’t have the EdmMetadata table and so won’t have the hash…and the implementation today will throw if that table is missing. We'll work on changing this behavior before we ship the fial version since it is the default. Until then, existing databases do not generally need any database initializer so it can be turned off for your context type by calling:

Database.SetInitializer<Production>(null);

Best Answer

Related Solutions

.net – Entity Framework 4 – Handling very large (1000+ tables) data models

C# – Entity Framework Code Only error: the model backing the context has changed since the database was created

Related Topic