How to use multiple filters to widen the search in Apachesolr queries - drupal

Question

Making a search with Apachesolr, i want to add a couple of filters in hook_apachesolr_prepare_query(&$query). This works fine, except I want the filters to widen the search ('OR'), rather than narrow it ('AND').
For example, if I have 4 nodes of type:A and 3 of type:B that match a search, to filter by type:A and type:B should return 7 nodes (of type:A AND nodes of type:B), rather than 0 those of type:A which are also of type:B.
I saw a suggestion to do this using the model of nodeaccess
foreach ($filters as $filter) {
$subquery = apachesolr_drupal_query();
if (!empty($subquery)) {
$subquery->add_filter('type', $filter);
$query->add_subquery($subquery);
}
}
but this doesn't seem to work. (It doesn't return any results).
I then tried (as I have a limited number of node types) excluding the types that I don't want:
$excludes = array('A', 'B', 'C');
$excludes = array_diff($excludes, $filters);
$exclude = implode('&', $excludes);
$query->add_filter('type', $exclude, TRUE);
This method of stitching them together doesn't work (the '&' gets escaped) but neither does adding them as subqueries, similar to the manner above.
Any suggestions on how to do this?

Answer 1

With Drupal7 and the last apacheSolr API, you can do OR filters by doing this :
function my_module_apachesolr_query_alter($query) {
// first, create a subQuery filter to store others
// and specify there is a "OR" condition
$filter = new SolrFilterSubQuery('OR');
// next, add all filters on bundle you want, each as
// a new subQuery filter, always with "OR" condition
// and add it to the primary filter
$a = new SolrFilterSubQuery('OR');
$a->addFilter('bundle', 'A');
$filter->addFilterSubQuery( $a );
$b = new SolrFilterSubQuery('OR');
$b->addFilter('bundle', 'B');
$filter->addFilterSubQuery( $b );
$c = new SolrFilterSubQuery('OR');
$c->addFilter('bundle', 'C');
$filter->addFilterSubQuery( $c );
// finally, add the primary subQuery filter as
// subquery of the current query
$query->addFilterSubQuery( $filter );
}
And your query search about type A OR type B OR type C (all results in each types). You can combine OR / AND by changing the parameter of the SolrFilterSubQuery instanciation.
Special thanks to this page and it's author : http://fr.ench.info/blog/2012/04/03/Add-Filters-ApacheSOLR.html

Answer 2

I havenť played with SOLR much but I am quiete familiar with Drupal and Zend Lucene (or Drupal Lucene API).
I would suggest that you try to filter your results based on content type (because each node has its content type stored in the object).
The second idea is to change basic operator. I am not sure how it is done in SOLR but i Zend Lucene
Zend_Search_Lucene_Search_QueryParser::setDefaultOperator($operator) and Zend_Search_Lucene_Search_QueryParser::getDefaultOperator() methods, respectively.
Docs can be found in Zend Lucene Docs. Or for SOLR Solr Docs.
I hope a got your problem right.
Hope it helps :-)