retrieve datefield value from document

[Mingfeng Yang]

I have an index first built with solr1.4 and later upgraded to solr3.6,
which has 150million documents, and all docs have a datefield which are not
blank. (verified by solr query).

I am using the following code snippet to retrieve

import org.apache.lucene.index.IndexReader;
import org.apache.lucene.store.*;
import org.apache.lucene.document.*;

IndexReader input = IndexReader.open(indexDir);
Document d = input.document(i);
int maxDoc = input.maxDoc();
for (int i = 0; i < maxDoc; i++) {
    System.out.println(d.get('date');
}

However, about 100 million docs give null for d.get('date') and about other
50 million docs give the right values.

What could be wrong?

Ming-