Lucene.NET and searching on multiple fields with specific values

Question

I've created an index with various bits of data for each document I've added, each document can differ in it field name.

Later on, when I come to search the index I need to query it with exact field/ values - for example:

FieldName1 = X AND FieldName2 = Y AND FieldName3 = Z

What's the best way of constructing the following using Lucene .NET:

• What analyser is best to use for this exact match type?
• Upon retrieving a match, I only need one specific field to be returned (which I add to each document) - should this be the only one stored?
• Later on I'll need to support keyword searching (so a field can have a list of values and I'll need to do a partial match).

The fields and values come from a Dictionary<string, string> . It's not user input, it's constructed from code.

Thanks,
Kieron

Answer 1

Well, I figured it out eventually - here's my take on it (this could be completely wrong, but it works for):

public Guid? Find (Dictionary<string, string> searchTerms)
{
    if (searchTerms == null)
        throw new ArgumentNullException ("searchTerms");

    try
    {
            var directory = FSDirectory.Open (new DirectoryInfo (IndexRoot));
            if (!IndexReader.IndexExists (directory))
                return null;

            var mainQuery = new BooleanQuery ();
            foreach (var pair in searchTerms)
            {
                var parser = new QueryParser (
                    Lucene.Net.Util.Version.LUCENE_CURRENT, pair.Key, GetAnalyzer ());
                var query = parser.Parse (pair.Value);

                mainQuery.Add (query, BooleanClause.Occur.MUST);
            }

            var searcher = new IndexSearcher (directory, true);

            try
            {
                var results = searcher.Search (mainQuery, (Filter)null, 10);
                if (results.totalHits != 1)
                    return null;

                return Guid.Parse (searcher.Doc (results.scoreDocs[0].doc).Get (ContentIdKey));
            }
            catch
            {
                throw;
            }
            finally
            {
                if (searcher != null)
                    searcher.Close ();
            }
    }
    catch
    {
            throw;
    }
}