Question

I am using EF 5 with migrations and code first. It all works rather nicely, but there are some issues/questions I would like to resolve.

Let s start with a simple example. Lets say I have a User table and a user type table. The user type table is an enum/lookup table in my app. So the user table has a UserTypeId column and a foreign key ref etc to UserType. In my poco, I have a property called UserType which has the enum type.

To add the initial values to the UserType table (or add/change values later) and to create the table in the initial migrator etc. I need a UserType table poco to represent the actual table in the database and to use in the map files. I mapped the UserType property in the User poco to UserTypeId in the UserType poco. So now I have a poco for code first/migrations/context mapping etc and I have an enum. Can t have the same name for both, so do I have a poco called UserType and something else for the enum or have the poco for UserType be UserTypeTable or something?

More importantly however, am I missing some key element in how code first works? I tried the example above, ran Add-Migration and it does not add the lookup table for the enum.

Answer 1

If I understood properly your questions and what you re confused about,

Enums support has nothing to do with lookup tables on the Db side.

Enums are simply allowing you to have properties in your classes that are Enum-s and that is translated into int -s basically - so there is nothing much else in there.

For more info you might wanna look at this video from Julie Lerman on Enum-s support

hope this helps

Answer 2

In my experience the enum is more important to your code than the lookup class so give it the proper name. I would also keep the look up class isolated without any relationship to the User in my Model. If it trully is only for lookup, then you don t need it hanging off of your User. Your enum with a DescriptionAttribute can fulfill the lookup in your code.

UserTypeLookup might be a good name since that sounds like what you will be using it for. Then you can use that class to maintain the table.

Assuming you don t map the relationship between UserTypeLookup and User in ef code first, the only thing you should need to create in the DB manually is the foriegn key relationship between the UserType column in your User table and the PK from the UserTypeLookup table. UserTypeLookup can still be an entity and EF should still generate the DB table for it even if you don t setup any relationships for it.

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