public class PersonBrief
{
public int Id { get; set; }
public string Picture { get; set; }
public PersonBrief(Person person)
{
Id = person.Id;
Picture = person.Picture;
}
}
public class Person : PersonBrief
{
public string FullName { get; set; }
}
var results = session.Query<Person>()
.Select(x => new PersonBrief(x))
.ToList();
Assert.IsNull(results[0] as Person); // Fails
Is this a bug? If not, what would be the correct way to select only the fields i'm interested in?
It would work if you move the .ToList before the .Select, but that would be doing the work on the client.
If you want to do it on the server, you need to use As in your query, and you need a static index that does a TransformResults. See these docs.
Related
I'm new to RavenDB and I'm struggling with this simple (i guess) issue.
I have a Subscriber with a collection of Subscriptions. And I want to make search by Subscription's fields, and return related Subscriber.
Here are simplified class examples:
public class Subscriber
{
public string Email { get; set; }
public string Name { get; set; }
public string Phone { get; set; }
public List<Subscription> Subscriptions { get; set; }
}
public class Subscription
{
public Guid Id { get; set; }
public string EventType { get; set; }
}
I've tried to make an index, as it is said in RavenDB docs:
public class Subscriber_BySubscription : AbstractIndexCreationTask<Subscriber>
{
public Subscriber_BySubscription()
{
Map = subscribers => from subscriber in subscribers
from subscription in subscriber.Subscriptions
select new
{
subscription.EventType,
subscription.QueueName
};
}
}
But I'm not sure that this is what I need, since query by collection using Select and Contains doesn't work. Moreover, the code looks so ugly that I feel that this is not the way how it should be.
So, I'd like to query Subscriptions by EventType, and have corresponding Subscriber as a result. In LINQ it would look like this: subscribers.Where(x => x.Subscriptions.Select(c => c.EventType).Contains(myEventType))
Managed to do it. Here is the right index:
public class Subscriber_BySubscription : AbstractIndexCreationTask<Subscriber>
{
public class Result
{
public string EventType { get; set; }
}
public Subscriber_BySubscription()
{
Map = subscribers => from subscriber in subscribers
from subscription in subscriber.Subscriptions
select new
{
subscription.EventType
};
}
}
And that's how it should be used:
var results = uow.Session
.Query<Subscriber_BySubscription.Result, Subscriber_BySubscription>()
.Where(x => x.EventType == eventType)
.OfType<Subscriber>()
.ToList();
Let's say we have a document like this
public class Event
{
public string Id { get; set; }
public EntityDescriptor Venue { get; set; }
// Other properties omitted for simplicity
}
public class EntityDescriptor
{
public string Id { get; set; }
public string Name { get; set; }
}
And an index like this
public class Events : AbstractIndexCreationTask<Event>
{
public Events()
{
Map = items => from e in items
select new
{
Venue_Id = e.Venue.Id,
Venue_Name = e.Venue.Name
};
}
}
When trying to sort on Event.Venue.Id
session.Query<Event, Events>().Take(10).OrderBy(e => e.Venue.Id).ToArray();
the sent request is
/indexes/Events?&pageSize=10&sort=__document_id&SortHint-__document_id=String
Is this by design or a bug?
PS: OrderBy(e => e.Venue.Name) works as expected (sort=Venue_Name).
It's not a bug. __document_id is the special known field containing the ID of the document. It's there regardless of whether you have an .Id property.
edit
I misread your question. This indeed appears to be a bug. I recommend you send a simple repro case to the Raven forum and let them know which RavenDB version you're using.
I'm a complete noob to Fluent NHibernate, and I'm using the Query Object Pattern based on a recommendation. Which I'm also new to. I'll try to keep the code samples concise and helpful.
User class:
public class User {
public Guid ID { get; set; }
public string Name { get; set; }
}
Visibility:
public enum VisibilityType {
Anybody,
OwnersOnly,
Nobody
}
Car class:
public class Car {
public Guid ID { get; set; }
public VisibilityType Visibility { get; set; }
public ICollection<User> Owners { get; set; }
}
So I need to write a conditional restriction method for the query object. Return all cars that have VisibilityType.Public, but if a car has Visibility property value of VisibilityType.OwnersOnly, restrict the return to users who belong to that group.
Here's the current restriction method that I have working, but without the condition:
public class CarQueryObject
{
private User user { get; set; }
private const string OwnersProperty = "Owners";
private const string OwnersIDProperty = "Owners.ID";
public CarQueryObject RestrictToOwners()
{
// How do I add a conditional criteria here? Only restrict by owner
// if the QueryObject has VisibilityType.OwnersOnly? Note that it should
// *NOT* restrict VisibilityType.Anybody
CreateOwnersAlias();
Criteria.Add(Restrictions.Eq(OwnersIDProperty, user.Id));
return this;
}
public CarQueryObject JoinFetchOwned()
{
Criteria.SetFetchMode(OwnersProperty, FetchMode.Join);
return this;
}
public void CreateOwnersAlias()
{
Criteria.CreateAlias(OwnersProperty, OwnersProperty, JoinType.LeftOuterJoin);
JoinFetchOwned();
}
}
?_?
an idea to get shown cars
var carsShown = session.CreateCriteria<Car>()
.JoinAlias("Owner", "owner")
.Add(Expressions.Or(
Expression.Eq("Visibility", Visibility.Anybody),
Expression.Eq("Visibility", Visibility.OwnersOnly) && Expression.Eq("owner.Id", currentUser.Id)
))
.List<Car>();
I'm struggling with the include function in RavenDB. In my model I have a blog post that holds a list of comments. The comment class that's used in this list holds a reference to a user.
public class BlogPost
{
public string Id { get; set; }
public List<Comment> Comments { get; set; }
public BlogPost()
{
Comments = new List<Comment>();
}
}
public class Comment
{
public string Id { get; set; }
public string Text { get; set; }
public string UserId { get; set; }
}
What I want to do is to get the blogpost and get a list of comments with the details of the user that wrote the comment to display in the UI, without querying the server for every single user (N+1).
I would be happy with some pointers on how to solve this. Thanks!
You can do that using something like:
session.Include<BlogPost>(b=>b.Comments.Select(x=>x.UserId)).Load(1);
I think this page would answer your question.
You can load multiple documents at once:
var blogSpots = session.Include<BlogPost>(x => x.Comments.Select(x=>x.UserId))
.Load("blogspot/1234", "blogspot/4321");
foreach (var blogSpot in blogSpots)
{
foreach (var userId in blogSpot)
// this will not require querying the server!!!
var cust = session.Load<User>(userId);
}
I'm trying to use the TransformResults feature, and I can't get it to work. I'm not totally sure I understand this feature, perhaps there is another way to solve this problem. What I want is just the Id from the Order and the email addesses from the Customer and the Entrepreneur. I am happy for all tips that can take me in the right direction. Here is my code.
Document
public class OrderDocument
public string Id {get; set }
public EntrepreneurInfo EntrepreneurInfo { get; set; }
public CustomerInfo CustomerInfo { get; set; }
public OrderStatus CurrentOrderStatus { get; set; }
}
Info classes
public class EntrepreneurInfo
{
public string EntrepreneurDocumentId { get; set; }
public string Number { get; set; }
public string Name { get; set; }
}
public class CustomerInfo
{
public string CustomerDocumentId { get; set; }
public string Number { get; set; }
public string Name { get; set; }
}
The info classes are just subsets of a Customer and Entrepreneur documents respectively.
The Customer and Entrepreneur documents inherits from a base class ( AbstractOrganizationDocument) that has the EmailAddress property.
My Index
public class OrdersApprovedBroadcastingData :
AbstractIndexCreationTask<OrderDocument, OrdersApprovedBroadcastingData.ReduceResult>
{
public OrdersApprovedBroadcastingData()
{
this.Map = docs => from d in docs
where d.CurrentOrderStatus == OrderStatus.Approved
select new
{
Id = d.Id,
CustomerId = d.CustomerInfo.CustomerDocumentId,
EntrepreneurId = d.EntrepreneurInfo.EntrepreneurDocumentId
};
this.TransformResults = (db, orders) => from o in orders
let customer = db.Load<CustomerDocument>(o.CustomerId)
let entrepreneur = db.Load<EntrepreneurDocument>(o.EntrepreneurId)
select
new
{
o.Id,
o.CustomerId,
CustomerEmail = customer.EmailAddress,
o.EntrepreneurId,
EntrepreneurEmail = entrepreneur.EmailAddress
};
}
public class ReduceResult
{
public string Id { get; set; }
public string CustomerId { get; set; }
public string CustomerEmail { get; set; }
public string EntrepreneurId { get; set; }
public string EntrepreneurEmail { get; set; }
}
}
If I look at the result of this Index in Raven Studio I get null values for all fields except the Id. And finally here is my query.
Query
var items =
this.documentSession.Query<OrdersApprovedBroadcastingData.ReduceResult, OrdersApprovedBroadcastingData>()
.Select(x => new OrdersToBroadcastListItem
{
Id = x.Id,
CustomerEmailAddress = x.CustomerEmail,
EntrepreneurEmailAddress = x.EntrepreneurEmail
}).ToList();
Change your index to:
public class OrdersApprovedBroadcastingData : AbstractIndexCreationTask<OrderDocument>
{
public OrdersApprovedBroadcastingData()
{
Map = docs => from d in docs
where d.CurrentOrderStatus == OrderStatus.Approved
select new
{
};
TransformResults = (db, orders) =>
from o in orders
let customer = db.Load<CustomerDocument>(o.CustomerInfo.CustomerDocumentId)
let entrepreneur = db.Load<EntrepreneurDocument>(o.EntrepreneurInfo.EntrepreneurDocumentId)
select new
{
o.Id,
CustomerEmailAddress = customer.EmailAddress,
EntrepreneurEmailAddress = entrepreneur.EmailAddress
};
}
}
Your result class can simply be the final form of the projection, you don't need the intermediate step:
public class Result
{
public string Id { get; set; }
public string CustomerEmailAddress { get; set; }
public string EntrepreneurEmailAddress { get; set; }
}
You don't have to nest this class in the index if you don't want to. It doesn't matter either way. You can query either with:
var items = session.Query<Result, OrdersApprovedBroadcastingData>();
Or with
var items = session.Query<OrderDocument, OrdersApprovedBroadcastingData>().As<Result>();
Though, with the first way, the convention tends to be to nest the result class, so really it would be
var items = session.Query<OrderDocument.Result, OrdersApprovedBroadcastingData>();
Note in the index map, I am not including any properties at all. None are required for what you asked. However, if you want to add a Where or OrderBy clause to your query, any fields you might want to filter or sort on should be put in there.
One last thing - the convention you're using of OrderDocument, CustomerDocument, EntrepreneurDocument, is a bit strange. The usual convention is just Order, Customer, Entrepreneur. Think of your documents as the persisted form of the entities themselves. The convention you are using will work, it's just not the one usually used.