Indexing and Searching Date in Lucene

Question

I tried it to index date with DateTools.dateToString() method. Its working properly for indexing as well as searching.

But my already indexed data which has some references is in such a way that it has indexed Date as a new Date().getTime().

So my problem is how to perform RangeSearch Query on this data...

Any solution to this???

Thanks in Advance.

Answer 1

You need to use a TermRangeQuery on your date field. That field always needs to be indexed with DateTools.dateToString() for it to work properly. Here's a full example of indexing and searching on a date range with Lucene 3.0:

public class LuceneDateRange {
    public static void main(String[] args) throws Exception {
        // setup Lucene to use an in-memory index
        Directory directory = new RAMDirectory();
        Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_30);
        MaxFieldLength mlf = MaxFieldLength.UNLIMITED;
        IndexWriter writer = new IndexWriter(directory, analyzer, true, mlf);

        // use the current time as the base of dates for this example
        long baseTime = System.currentTimeMillis();

        // index 10 documents with 1 second between dates
        for (int i = 0; i < 10; i++) {
            Document doc = new Document();
            String id = String.valueOf(i);
            String date = buildDate(baseTime + i * 1000);
            doc.add(new Field("id", id, Store.YES, Index.NOT_ANALYZED));
            doc.add(new Field("date", date, Store.YES, Index.NOT_ANALYZED));
            writer.addDocument(doc);
        }
        writer.close();

        // search for documents from 5 to 8 seconds after base, inclusive
        IndexSearcher searcher = new IndexSearcher(directory);
        String lowerDate = buildDate(baseTime + 5000);
        String upperDate = buildDate(baseTime + 8000);
        boolean includeLower = true;
        boolean includeUpper = true;
        TermRangeQuery query = new TermRangeQuery("date",
                lowerDate, upperDate, includeLower, includeUpper);

        // display search results
        TopDocs topDocs = searcher.search(query, 10);
        for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
            Document doc = searcher.doc(scoreDoc.doc);
            System.out.println(doc);
        }
    }

    public static String buildDate(long time) {
        return DateTools.dateToString(new Date(time), Resolution.SECOND);
    }
}

Answer 2

You'll get much better search performance if you use a NumericField for your date, and then NumericRangeFilter/Query to do the range search.

You just have to encode your date as a long or int. One simple way is to call the .getTime() method of your Date, but this may be far more resolution (milli-seconds) than you need. If you only need down to the day, you can encode it as YYYYMMDD integer.

Then, at search time, do the same conversion on your start/end Dates and run NumericRangeQuery/Filter.