RavenDB Transformations and Joining Simple Data - join

Question

I was wondering if someone could help me understand RavenDB transformations as I cant seem to get them working correctly. I tried following Ayende's post but I am not able to apply it to my situation. I have two models, a UserModel and an UserAddressModel. The code is as follows
public class UserModel
{
#region Properties
public string Id { get; set; }
public string AccountId { get; set; }
public string UserName { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Email { get; set; }
public DateTime InsertDate { get; set; }
#endregion
}
and
public class UserAddressModel
{
public string Id { get; set; }
public string AccountId { get; set; }
public string Address1 { get; set; }
public string Address2 { get; set; }
public string City { get; set; }
public string State { get; set; }
public string Zipcode { get; set; }
public float Latitude { get; set; }
public float Longitude { get; set; }
public DateTime InsertDate { get; set; }
}
I have my RavenDB Index set up like such.
public class UserDashboard_ByName : AbstractIndexCreationTask<UserModel>
{
public UserDashboard_ByName()
{
Map = users => from user in users
select new { user.UserName, user.AccountId };
TransformResults =
(database, users) => from user in users
let useraddress = database.Load<UserAddressModel>(user.AccountId)
select new
{ FirstName = user.FirstName,
LastName = user.LastName,
Address1 = useraddress.Address1,
Address2 = useraddress.Address2
};
}
}
and I am calling it with the following code
using (var session = DataDocumentStore.Instance.OpenSession())
{
//Get the AccountId
var userDashboard =
(from user in session.Query<UserModel, UserDashboard_ByName>()
where user.UserName == userName
select user).SingleOrDefault();
}
When I call the index, it returns a UserModel type, not the anonymous type that I am expecting. Also, I do not understand how I can call
let useraddress = database.Load<UserAddressModel>(user.AccountId)
when there is no specific relationship that has been specified in code or anywhere else.
Maybe someone can explain to me how I should be joining data in RavenDB? Some expanded documentation or a nudge in the right direction to understanding this better would be greatly appreciated. Thanks in advance.

Answer 1

The problem is inside your TransformResult function where you call database.Load<UserAddressModel>(user.AccountId). You can only load the UserAddressModel with its id, not by a property like AccountId.
You have to store the id of the UserAddressModel inside your UserModel if you want to do it that way. However, I wouldn't model it in that way. UserAddressModel doesn't have any meaning on itself, so it should probably be part of UserModel. As a rule of thumb, you generally want to have your aggregrate roots as documents and everything else inside them.

Answer 2

You need to create another model (a view model basically), such as UserWithAddressModel that includes the 4 properties you wish to return:
public class UserWithAddressModel
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string Address1 { get; set; }
public string Address2 { get; set; }
}
Then do your query like this:
var userDashboard =
(from user in session.Query<UserModel, UserDashboard_ByName>()
where user.UserName == userName
select user).As<UserWithAddressModel>().SingleOrDefault();
I think this is what you are looking for.
UPDATE:
Try like this:
var userDashboard = session.Query<UserModel, UserDashboard_ByName>()
.Where(x => x.UserName == userName)
.As<UserWithAddressModel>()
.SingleOrDefault();
UPDATE2:
Sorry, just looked again at what you are trying to do, it won't work like that. I thought you had a reference to your UserAddressModel in your UserModel (such as UserAddressId).
Why are you splitting the 2 models up in the first place if they are a 1:1 relation?