Zend\_Search\_Lucene (or Lucene in general) does not support an update statement, therefore we must check via find() if a specific article that should be updated already exists.
Numerous solutions exist for this problem (for example this PDF Tutorial by a Zend Programmer). Mine looks as follows. The first thing is to Set an Analyzer other from the default one. The Default Analyzer only looks at letters, not at numbers.
Zend_Search_Lucene_Analysis_Analyzer::setDefault(new
Zend_Search_Lucene_Analysis_Analyzer_Common_Utf8Num_CaseInsensitive()
);
$index = Zend_Search_Lucene::open('/path/to/index/directory');
We can now save an identifier containing letters and numbers, for example the md5 string of the Article Database ID.
$doc = new Zend_Search_Lucene_Document();
$field = Zend_Search_Lucene_Field::Keyword('id', md5($data['id']));
$doc->addField($field);
$index->addDocument($doc);
Before updating an entry you have to delete any entry that has been indexed before:
$hits = $index->find('id:'.md5($articleID));
foreach($hits AS $hit) {
$index->delete($hit->id);
}
The Tutorial Talk on Search Lucene (given above) uses an extended version of this delete routine snippet that also checks if an article is up to date and does not have to be reindexed and deletes multiple entries of one article.