RavenDB Index no longer returning results - ravendb

Question

I'm attempting to apply Ayende's order search from here to an existing index.
The current index looks like this:
public class HomeBlurb_IncludeTotalCosts_Search2 : AbstractIndexCreationTask<MPDocument, HomeBlurb_IncludeTotalCosts_Search2.ReduceResult>
{
public class ReduceResult
{
public string Name { get; set; }
public string Constituency { get; set; }
public decimal? AmountPaid { get; set; }
}
public HomeBlurb_IncludeTotalCosts_Search2()
{
Map = mps => from mp in mps
from exp in mp.Expenses
select new
{
mp.Name,
mp.Constituency,
exp.AmountPaid
};
Reduce = results => from result in results
group result by new { result.Name, result.Constituency } into g
select new
{
Name = g.Key.Name,
Constituency = g.Key.Constituency,
AmountPaid = g.Sum(x => x.AmountPaid)
};
Index(x => x.Name, FieldIndexing.Analyzed);
Index(x => x.Constituency, FieldIndexing.Analyzed);
}
}
This index works fine. However when I try to change the Map to:
from mp in mps
from exp in mp.Expenses
select new
{
Query = new object[]{mp.Name,mp.Constituency},
mp.Name,
mp.Constituency,
exp.AmountPaid
};
and the reduce to
from result in results
group result by new { result.Name, result.Constituency } into g
select new
{
Query = "",
Name = g.Key.Name,
Constituency = g.Key.Constituency,
AmountPaid = g.Sum(x => x.AmountPaid)
};
I then get no results when querying on the Query property. If I remove the reduce the index returns data, but it always returns the full MPDocument, which is much more that I was to materialise. Is there a way to use the technique described in the original post that also utilises a reduce?

Answer 1

You can use this in your reduce function:
Query = g.Select(x => x.Query).Where(x => x != null).FirstOrDefault()
In order to query on that field, you need to have a seperate query model and a result model. Here is a full example using your code:
public class MultiTermFieldInMapReduce
{
public class MPDocument
{
public List<Epense> Expenses { get; set; }
public string Name { get; set; }
public string Constituency { get; set; }
public class Epense
{
public decimal? AmountPaid { get; set; }
}
}
public class HomeBlurb_IncludeTotalCosts_Search2 : AbstractIndexCreationTask<MPDocument, HomeBlurb_IncludeTotalCosts_Search2.ReduceResult>
{
public class ReduceResult
{
public string Name { get; set; }
public string Constituency { get; set; }
public decimal? AmountPaid { get; set; }
public object[] Query { get; set; }
}
public class SearchModel
{
public string Name { get; set; }
public string Constituency { get; set; }
public decimal? AmountPaid { get; set; }
public string Query { get; set; }
}
public HomeBlurb_IncludeTotalCosts_Search2()
{
Map = mps => from mp in mps
from exp in mp.Expenses
select new
{
mp.Name,
mp.Constituency,
exp.AmountPaid,
Query = new object[]
{
mp.Name,
mp.Constituency
}
};
Reduce = results => from result in results
group result by new { result.Name, result.Constituency } into g
select new
{
Name = g.Key.Name,
Constituency = g.Key.Constituency,
AmountPaid = g.Sum(x => x.AmountPaid),
Query = g.Select(x => x.Query).Where(x => x != null).FirstOrDefault()
};
Index(x => x.Name, FieldIndexing.Analyzed);
Index(x => x.Constituency, FieldIndexing.Analyzed);
}
}
[Fact]
public void Query_returns_results()
{
using (var store = new EmbeddableDocumentStore { RunInMemory = true }.Initialize())
{
using (var session = store.OpenSession())
{
session.Store(new MapReduceError.MPDocument
{
Name = "test1",
Expenses = new List<MapReduceError.MPDocument.Epense>
{
new MapReduceError.MPDocument.Epense {AmountPaid = 5.5m},
new MapReduceError.MPDocument.Epense {AmountPaid = 5.5m},
new MapReduceError.MPDocument.Epense {AmountPaid = 5.5m},
new MapReduceError.MPDocument.Epense {AmountPaid = 5.5m}
}
});
session.Store(new MapReduceError.MPDocument
{
Name = "test2",
Expenses = new List<MapReduceError.MPDocument.Epense>
{
new MapReduceError.MPDocument.Epense {AmountPaid = 10},
new MapReduceError.MPDocument.Epense {AmountPaid = 10},
new MapReduceError.MPDocument.Epense {AmountPaid = 10},
new MapReduceError.MPDocument.Epense {AmountPaid = 10}
}
});
session.SaveChanges();
}
new HomeBlurb_IncludeTotalCosts_Search2().Execute(store);
using (var session = store.OpenSession())
{
var results =
session.Query
<HomeBlurb_IncludeTotalCosts_Search2.SearchModel, HomeBlurb_IncludeTotalCosts_Search2>()
.Customize(x => x.WaitForNonStaleResultsAsOfLastWrite())
.Where(x => x.Query == "test1")
.As<HomeBlurb_IncludeTotalCosts_Search2.ReduceResult>()
.ToList();
Assert.Equal(1, results.Count);
Assert.Equal(22, results.First().AmountPaid);
}
}
}
}

Answer 2

I don't think you need a Map/Reduce index to do this, you seem to only be reducing on MPDocument Name and Constituency, which I guess are unique to each MP.
I think that you want to use TransformResults, so that you can change the shape of the output instead, something like so:
TransformResults =
(database, mps) => from mp in mps
select new
{
mp.Name,
mp.???
< JUST THE BITS YOU WANT RETURNED >
};
Then you query like so:
session.Query<mp>("index name")
.Where(..)
.As<MPQueryResult>()
.ToList()