* To be sure the datastoreProvider retrieves only the columns we want,
* an extra column is manually added to the association document
*/
protected void addExtraColumn() {
MongoDBDatastoreProvider provider = (MongoDBDatastoreProvider) this.getService( DatastoreProvider.class );
DB database = provider.getDatabase();
DBCollection collection = database.getCollection( "associations_Project_Module" );
BasicDBObject query = new BasicDBObject( 1 );
query.put( "_id", new BasicDBObject( "Project_id", "projectID" ) );
BasicDBObject updater = new BasicDBObject( 1 );
updater.put( "$push", new BasicDBObject( "extraColumn", 1 ) );