RavenDB Upgrade: 2.5 to 3.5 - Cannot compile index

Question

I'm currently in the process of upgrading our Solution from RavenDB 2.5 to 3.5 but getting the following exception when creating indexes: Looks like it has something to do with the group by

IndexCreation.CreateIndexes(typeof(RavenGuid).Assembly, store);

Index Definition

public RecordingArtistTypeaheadIndex()
{
    Map = docs => docs.Select(x => new Definition { Artist = x.ArtistDisplayName });

    Reduce = results => results.SelectMany(r => r.Artist.Split('|')).GroupBy(x => x).Select(g => new Definition { Artist = g.Key });

    Store(x => x.Artist, FieldStorage.Yes);

    Index(x => x.Artist, FieldIndexing.Analyzed);
}

Exception message

Compilation Errors:

Line 40, Position 11: Error CS1525 - Invalid expression term 'by'
Line 40, Position 14: Error CS0745 - Expected contextual keyword 'by'

Source code

public class Index_RecordingArtistTypeaheadIndex : Raven.Database.Linq.AbstractViewGenerator
{
    public Index_RecordingArtistTypeaheadIndex()
    {
        this.ViewText = @"from x in docs.RepertoireResources
                          select new {
                              Artist = x.ArtistDisplayName
                          }
                          from x in results.SelectMany(r => r.Artist.Split(new char[] {'|'}))
                          group x by x into g
                          select new {
                              Artist = g.Key
                          }";

        this.ForEntityNames.Add("RepertoireResources");

        this.AddMapDefinition(docs => 
            from x in ((IEnumerable<dynamic>)docs)
            where string.Equals(x["@metadata"]["Raven-Entity-Name"], "RepertoireResources", System.StringComparison.InvariantCultureIgnoreCase)
            select new {
                Artist = x.ArtistDisplayName,
                __document_id = x.__document_id
            });

        this.ReduceDefinition = results => 
            from x in results.SelectMany((Func<dynamic, IEnumerable<dynamic>>)(r => (IEnumerable<dynamic>)(r.Artist.Split(new char[] {
                '|'
            }))))
            group  by x into g
            select new {
                Artist = g.Key
            };

        this.GroupByExtraction = x => x;
        this.AddField("Artist");
        this.AddQueryParameterForMap("ArtistDisplayName");
        this.AddQueryParameterForMap("__document_id");
        this.AddQueryParameterForReduce("ArtistDisplayName");
        this.AddQueryParameterForReduce("__document_id");
    }
}

Has anyone came across this before?

You aren't grouping. What are you using Map/Reduce index for ? `GroupBy(x => x)` — Ayende Rahien, Feb 13 '17 at 08:21
I'm using the groupby to remove duplicates :) Perhaps a cheat. — FaNIX, Feb 13 '17 at 11:42

score 1 · Accepted Answer · answered Feb 13 '17 at 17:58

Solution: I changed the reduce so that the SelectMany returns an anonymous type and then I use the .Artist property in the GroupBy

public RecordingArtistTypeaheadIndex()
{
    Map = docs => docs.Select(x => new Definition
    {
        Artist = x.ArtistDisplayName
    });

    Reduce = results => results
        .SelectMany(r => r.Artist.Split('|'), (x, y) => new Definition { Artist = y })
        .GroupBy(x => x.Artist)
        .Select(g => new Definition
        {
            Artist = g.Key
        });

    Store(x => x.Artist, FieldStorage.Yes);

    Index(x => x.Artist, FieldIndexing.Analyzed);
}

RavenDB Upgrade: 2.5 to 3.5 - Cannot compile index

1 Answers1