BooleanQuery not working using Lucene.net 3.0.3

Question

Why the first query works but the second does not when using BooleanQuery on Lucene.net?

Here is a sample Indexed on field SHOPPING:

Shoes for sale

Great bargain on shoes and accessories.

Buy cheap Shoes, Sneekers and Heels!

First Query (works well, it returns all three indexed).

Query query = MultiFieldQueryParser.Parse(Lucene.Net.Util.Version.LUCENE_30, 
    "Shoes", new String[] { "SHOPPING" }, new Occur[] { Occur.SHOULD }, 
     new SimpleAnalyzer()
);
hits = indexSearcher.search(query);

Second Query (returns nothing, condition is: return all terms with 'shoes' BUT without 'accessories').

Query query1 = new TermQuery(new Term("SHOPPING", "shoes"));
Query query2 = new TermQuery(new Term("SHOPPING", "accessories"));

BooleanQuery booleanQuery = new BooleanQuery();
booleanQuery.Add(query1, Occur.SHOULD);
booleanQuery.Add(query2, Occur.MUST_NOT);

hits = indexSearcher.search(booleanQuery);

score 1 · Answer 1 · answered Dec 17 '15 at 04:13

I think I got it. Suppose to combine MultiFieldQueryParser and BooleanQuery do the trick.

    Query query = MultiFieldQueryParser.Parse(Lucene.Net.Util.Version.LUCENE_30, "Shoes", new String[] { "SHOPPING" }, new SimpleAnalyzer());

    Query queryOrig = parser.Parse("shoes");
    Query queryOrig2 = parser.Parse("accessories");

    var booleanQuery= new BooleanQuery();
    booleanQuery.Add(queryOrig, Occur.MUST);
    booleanQuery.Add(queryOrig2, Occur.MUST_NOT);

    hits = indexSearcher.search(booleanQuery);

typo? the "query" in the first line isn't used. If you're going to use parsers though you may as well use the standard parser and just search for "shoes NOT accessories" rather than using the Query based lower level stuff — AndyPook, Mar 21 '16 at 18:24

AndyPook · Answer 2 · 2016-03-22T20:38:07.233

Further to my comment to your earlier answer... here's the code for a couple of unit tests that shows a worked example. The first test uses a parser. The second the Query object version

[TestClass]
public class UnitTest6
{
    [TestMethod]
    public void TestShopping()
    {
        var writer = CreateIndex();
        Add(writer, "Shoes for sale");
        Add(writer, "Great bargain on shoes and accessories.");
        Add(writer, "Buy cheap Shoes, Sneekers and Heels!");
        writer.Flush(true, true, true);

        var searcher = new IndexSearcher(writer.GetReader());
        var result1 = Search(searcher, "shoes NOT accessories");

        Assert.AreEqual(2, result1.Count);
        Assert.IsTrue(result1.Contains("Shoes for sale"));
        Assert.IsTrue(result1.Contains("Buy cheap Shoes, Sneekers and Heels!"));

        writer.Dispose();
    }
    [TestMethod]
    public void TestShopping2()
    {
        var writer = CreateIndex();
        Add(writer, "Shoes for sale");
        Add(writer, "Great bargain on shoes and accessories.");
        Add(writer, "Buy cheap Shoes, Sneekers and Heels!");
        writer.Flush(true, true, true);

        var searcher = new IndexSearcher(writer.GetReader());

        var query1 = new TermQuery(new Term("shopping", "shoes"));
        var query2 = new TermQuery(new Term("shopping", "accessories"));

        var booleanQuery = new BooleanQuery();
        booleanQuery.Add(query1, Occur.SHOULD);
        booleanQuery.Add(query2, Occur.MUST_NOT);

        var result1 = Search(searcher, booleanQuery);

        Assert.AreEqual(2, result1.Count);
        Assert.IsTrue(result1.Contains("Shoes for sale"));
        Assert.IsTrue(result1.Contains("Buy cheap Shoes, Sneekers and Heels!"));

        writer.Dispose();
    }

    private void Test(IndexSearcher searcher, string query)
    {
        var result = Search(searcher, query);
        Console.WriteLine(string.Join("\n", result));
        Assert.AreEqual(1, result.Count);
    }

    private List<string> Search(IndexSearcher searcher, string expr)
    {
        var analyzer = new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30);
        var queryParser = new QueryParser(Lucene.Net.Util.Version.LUCENE_30, "shopping", analyzer);
        var query = queryParser.Parse(expr);
        return Search(searcher, query);
    }
    private List<string> Search(IndexSearcher searcher, Query query)
    {
        var collector = TopScoreDocCollector.Create(1000, true);

        searcher.Search(query, collector);

        var result = new List<string>();
        var matches = collector.TopDocs().ScoreDocs;
        foreach (var item in matches)
        {
            var id = item.Doc;
            var doc = searcher.Doc(id);
            result.Add(doc.GetField("shopping").StringValue);
        }
        return result;
    }

    IndexWriter CreateIndex()
    {
        var directory = new RAMDirectory();

        var analyzer = new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30);
        var writer = new IndexWriter(directory, analyzer, new IndexWriter.MaxFieldLength(1000));

        return writer;
    }
    void Add(IndexWriter writer, string text)
    {
        var document = new Document();
        document.Add(new Field("shopping", text, Field.Store.YES, Field.Index.ANALYZED));

        writer.AddDocument(document);
    }
}

BooleanQuery not working using Lucene.net 3.0.3

2 Answers2