Lucene and Special Characters

Posted by Brandon on Stack Overflow See other posts from Stack Overflow or by Brandon
Published on 2010-04-28T20:39:52Z Indexed on 2010/04/28 20:47 UTC
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I am using Lucene.Net 2.0 to index some fields from a database table. One of the fields is a 'Name' field which allows special characters. When I perform a search, it does not find my document that contains a term with special characters.

I index my field as such:

Directory DALDirectory = FSDirectory.GetDirectory(@"C:\Indexes\Name", false);
Analyzer analyzer = new StandardAnalyzer();
IndexWriter indexWriter = new IndexWriter(DALDirectory, analyzer, true, IndexWriter.MaxFieldLength.UNLIMITED);

Document doc = new Document();
doc.Add(new Field("Name", "Test (Test)", Field.Store.YES, Field.Index.TOKENIZED));
indexWriter.AddDocument(doc);

indexWriter.Optimize();
indexWriter.Close();

And I search doing the following:

value = value.Trim().ToLower();
value = QueryParser.Escape(value);

Query searchQuery = new TermQuery(new Term(field, value));
Searcher searcher = new IndexSearcher(DALDirectory);

TopDocCollector collector = new TopDocCollector(searcher.MaxDoc());
searcher.Search(searchQuery, collector);
ScoreDoc[] hits = collector.TopDocs().scoreDocs;

If I perform a search for field as 'Name' and value as 'Test', it finds the document. If I perform the same search as 'Name' and value as 'Test (Test)', then it does not find the document.

Even more strange, if I remove the QueryParser.Escape line do a search for a GUID (which, of course, contains hyphens) it finds documents where the GUID value matches, but performing the same search with the value as 'Test (Test)' still yields no results.

I am unsure what I am doing wrong. I am using the QueryParser.Escape method to escape the special characters and am storing the field and searching by the Lucene.Net's examples.

Any thoughts?

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