What is the correct way of using Entity Framework?

I have a DB like this that I generated from EF:

Now I'd like to add a "fielduserinput" entity so I write the following code:

    public bool AddValueToField(string field, string value, string userId)
    {
        //adds a value to the db
        var context = new DBonlyFieldsContainer();
        var fieldSet = (from fields in context.fieldSet
                        where fields.fieldName.Equals(field)
                        select fields).SingleOrDefault();
        var userSet = (from users in context.users
                       where users.id.Equals(userId)
                       select users).SingleOrDefault();

        var inputField = new fielduserinput { userInput = value, field = fieldSet, user = userSet };
        return false;
    }

Obviously it's not finished but I think it conveys what I'm doing.

Is this really the right way of doing this? My goal is to add a row to fielduserinput that contains th开发者_高级运维e value and references to user and field. It seems a bit tedious to do it this way. I'm imagining something like:

public bool AddValueToField(string userId, string value, string fieldId)
{
    var context = new db();
    var newField = { field.fieldId = idField, userInput = value, user.id = userId }
    //Add and save changes
}

For older versions of EF, I think you're doing more or less what needs to be done. It's one of the many reasons I didn't feel EF was ready until recently. I'm going to lay out the scenario we have to give you another option.

We use the code first approach in EF 4 CTP. If this change is important enough, read on, wait for other answers (because Flying Speghetti Monster knows I could be wrong) and then decide if you want to upgrade. Keep in mind it's a CTP not an RC, so considerable changes could be coming. But if you're starting to write a new application, I highly recommend reading some about it before getting too far.

With the code first approach, it is possible to create models that contain properties for a reference to another model and a property for the id of the other model (User & UserId). When configured correctly setting a value for either the reference or the id will set the id correctly in the database.

Take the following class ...

public class FieldUserInput{
    public int UserId {get;set;}
    public int FieldId {get;set;}

    public virtual User User {get;set;}
    public virtual Field Field {get;set;}
}

... and configuration

public class FieldUserInputConfiguration{
    public FieldUserInputConfiguration(){
        MapSingleType(fli => new {
            userid = fli.UserId,
            fieldid = fli.FieldId
        };
        HasRequired(fli => fli.User).HasConstraint((fli, u)=>fli.UserId == u.Id);
        HasRequired(fli => fli.Field).HasConstraint((fli, f)=>fli.FieldId == f.Id);
    }
}

You can write the code...

public void CreateField(User user, int fieldId){
    var context = new MyContext();
    var fieldUserInput = new FieldUserInput{ User = user, FieldId = fieldId };
    context.FieldUserInputs.Add(fieldUserInput);
    context.SaveChanges();
}

... or vice versa with the properties and everything will work out fine in the database. Here's a great post on full configuration of EF.

Another point to remember is that this level of configuration is not necessary. Code first is possible to use without any configuration at all if you stick to the standards specified in the first set of posts referenced. It doesn't create the prettiest names in the database, but it works.

Not a great answer, but figured I'd share.