Question

I have something that looks like the following document structure:

public class Document {
    public int Id { get; set; }
    public string Name { get; set; }
    public List<Property> Properties { get; set; }
}

public class Property {
    public int Id { get; set; }
    public string Name { get; set; }
}

Now, querying and modifying Documents is easy. But I need to access specific Property-instances in my app, and it seems that they won’t automatically get an ID like the root document does. And it seems this is by design in RavenDB.

I might be me stuck in the relational world, but what I’d like to do is basically retrieve the correct document, then get the right property, modify it and save the document again.

from property in document.Properties 
where property.Id == someId
select property

…which will obviously not work as long as

• RavenDB does not auto-set the Id field or
• I don’t make any ID-generating mechanism myself

Am I heading completely the wrong way, or does what I’m trying to do mak sense? Should I move the Properties out to being a root node and make some sort of reference to them in Document? Or should I just do something like this when inserting properties:

1. Retrieve the document with the list of properties
2. Get Properties[last]’s ID
3. Add 1 and insert new ID myself in new properties

?

This would, however, require at least two requests (one to get existing properties, one to save the changes) to the database, which just seems dirty and unnecessarsy for such a seemingly simple task.

I’ve found a lot of sortof similar posts, but none of them really answers this AFAIK.

Answer 1

Check to see how we do that in RaccoonBlog:
https://github.com/ayende/RaccoonBlog/blob/master/RaccoonBlog.Web/Infrastructure/Tasks/AddCommentTask.cs