lucene.net 如果搜索词没有 space 则匹配

Question

我正在使用 lucene.net 在我的 c# asp.net 应用程序的帖子中执行搜索，这是我索引中的示例文档：

var doc = new Document();
var title = new Field("Title", "the album hardwired to self-destruct released", Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS);
title.Boost = 5;
doc.Add(title);
var ns_title = new Field("NoSpace_Title", "thealbumhardwiredtoselfdesctructreleased", Field.Store.NO, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS);
ns_title.Boost = 5;
doc.Add(ns_title);
doc.Add(new Field("Body", "the body text of the post", Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS));
doc.Add(new Field("Id", "1", Field.Store.YES, Field.Index.NOT_ANALYZED));
writer.AddDocument(doc);

问题:
如果我搜索 self 或 destruct 或 self destruct 我会被击中。
如果我搜索 selfdestruct 我没有找到。

搜索方式:

var searchWords = s.Split(' ').ToList();
var directory = GetDirectory();
var reader = IndexReader.Open(directory, true);
var searcher = new IndexSearcher(reader);
var analyzer = new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30);
var parser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_30, "Title,NoSpace_Title,Body".Split(','), analyzer);
var booleanQuery = new BooleanQuery();

// Title:selfdestruct*NoSpace_Title:selfdestruct*Body:selfdestruct*
s = string.Join(" ", searchWords.Select(x => x.Contains("*") ? x : x + "*"));
Query query = parser.Parse(QueryParser.Escape(s));
query.Boost = 5;
booleanQuery.Add(query, Occur.SHOULD);

// Title:*selfdestruct*,NoSpace_Title:*selfdestruct*,Body:*selfdestruct*
// (I suppose this should work and get hit but it doesn't)
s = "*" + string.Join("", searchWords) + "*";
Query query2 = parser.Parse(QueryParser.Escape(s));
query2.Boost = 3;
booleanQuery.Add(query2, Occur.SHOULD);

// Title:selfdestruct~0.85 (fuzzy search)
s = string.Join(" ", searchWords.Select(x => x.Contains("~") ? x : x + "~0.85"));
Query query3 = parser.Parse(QueryParser.Escape(s));
booleanQuery.Add(query3, Occur.SHOULD);

var collector = TopScoreDocCollector.Create(1000, true);
searcher.Search(booleanQuery, collector);
var hits = collector.TopDocs().ScoreDocs;
var docs = hits.Select(x => searcher.Doc(x.Doc)).ToList();

Answer 1

您可以通过在分析器中添加 ShingleFilter 来支持这一点。

ShingleFilter 会将相邻的标记组合成单个标记，以便于在没有 space 的情况下搜索它们。默认情况下，它也会输出 Unigrams（也就是说，它还会保留单个标记）。因此，当您索引 "self-destruct" 时，它将索引标记 "self"、"destruct" 和 "selfdestruct".

在不创建您自己的自定义分析器的情况下执行此操作的简单方法是使用 ShingleAnalyzerWrapper:

var analyzer = new ShingleAnalyzerWrapper(
        new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30),
        2);

lucene.net 如果搜索词没有 space 则匹配

lucene.net match if search term has no space

c#

lucene

asp.net-mvc

lucene.net