RavedDB "outerjoin" - ravendb

Question

I have 2 collections of documents in my ravenDB, location and address like this:
public class Location()
{
public string Id{get;set;}
public string Name{get;set;}
public List<Address> Addresses{get;set;}
}
public class Address()
{
public string Id{get;set;}
public string StreetName {get;set;}
public string PostalCode {get;set;}
}
So a Location can have zero og many addresses. And I can have many addresses that are not assigned to a Location.
If I have data like this:
//2 Location document
{
Id:"Location/1",
Name: "My Location 1"
Addresses: [{id:"Address/1"},
{id:"Address/2"}
]
}
{
Id:"Location/2",
Name: "My Location 2"
Addresses: [
{id:"Address/2"}
]
}
//3 Address document
{
Id: "Address/1",
StreetName: "Street1 10",
PostalCode: "1000"
}
{
Id: "Address/2",
StreetName: "Street1 11",
PostalCode: "1000"
}
{
Id: "Address/3",
StreetName: "Street1 12",
PostalCode: "2000"
}
I'm struggleing to find the best way to create an index of this which will give me a resultset like this:
StreetAddress PostalCode Location
Street1 10 1000 My Location 1
Street2 11 1000 My Location 2
Street2 11 1000 My Location 1
Street3 12 2000
I would appreciate any input on this:-)

Answer 1

One option is to model the other way around, i.e.
public class Location()
{
public string Id {get;set;}
public string Name {get;set;}
}
public class Address()
{
public string Id {get;set;}
public string StreetName {get;set;}
public string PostalCode {get;set;}
// Locations is a list with the Location documents IDs
public List<string> Locations {get;set;}
}
And then the index can be:
from address in docs.Addresses
select new {
StreetAddress = address.StreetName,
PostalCode = address.PostalCode
}
And then use the following Query:
from index 'AddressesIndex' as x
load x.Locations as locations[]
select {
StreetName: x.StreetName,
PostalCode: x.PostalCode,
Locations: locations.map(x => x.Name)
}
===========================================================================
A second option is to use the same models as you have in the question description
and define a multi-map-reduce index.
The multi-map-reduce index will be:
The first map:
from locationDoc in docs.Locations
from addressId in locationDoc.Addresses
let address = LoadDocument(addressId, "Addresses")
select new {
StreetName = address.StreetName,
PostalCode = (string)null,
LocationNames = new []{locationDoc.Name},
}
The second map:
from address in docs.Addresses
select new{
StreetName = address.StreetName,
PostalCode = address.PostalCode,
LocationNames = (string)null
}
The reduce:
from result in results
group result by new { result.StreetName } into g
select new {
StreetName = g.Key.StreetName,
PostalCode = g.Select(x => x.PostalCode).FirstOrDefault(x => x != null),
LocationNames = g.SelectMany(x => x.LocationNames)
}