Can RavenDB faceted search somehow break down a facet into sub-facets?

Question

I am pretty new to faceted search, so it is kind of difficult for me to wrap my head around this... but here goes:

Pretend I have Item which contains a collection of SubItems and the SubItem has an enum that indicates a status - I have successfully enabled faceted search on categories on both Item and SubItem using this index definition:

public class FacetIndexItems : AbstractIndexCreationTask<Item>
{
    public const string FacetId = "facets/Items";
    public const string ItemCategoryFacetName = "Category";
    public const string SubItemCategoryFacetName = "SubItems_Category";

    public FacetIndexItems()
    {
        Map = items => from item in items
                       from subItem in item.SubItems
                       select new
                                  {
                                      Category = item.Category,
                                      SubItems_Category = subItem.Category
                                  };
    }
}

and this FacetSetup:

new FacetSetup
{
    Id = FacetIndexItems.FacetId,
    Facets =
        {
            new Facet {Name = FacetIndexItems.ItemCategoryFacetName},
            new Facet {Name = FacetIndexItems.SubItemCategoryFacetName}
        }
}

So far, so good!

Now, pretend that SubItem has a Status property - is there a way to divide the result of each facet into different statuses?

E.g. so that quering this data:

{
    Category: "wut", 
    SubItems: [
       {Category: "bim", Status: "good"},
       {Category: "bim", Status: "good"},
       {Category: "bim", Status: "bad"}
    ]
}

by item.Category.In("wut") && item.SubItems.Any(s => s.Category.In("bim")) would yield a result like

{
    Category: {
        "good": 2
        "bad": 1
    },
    SubItems_Category: {
        "good": 2
        "bad": 1
    }
}

I am unsure whether this is actually possible to do with faceted search, and I am definitely open to alternatives if my approach is wrong.

Answer 1

You would have to generate different values for each option, you can't do a facet on more than one field at a time. But you can generate fields at indexing time, so that does the same thing.