protected void addExtraColumn() {
MongoDBDatastoreProvider provider = (MongoDBDatastoreProvider) super.getService( DatastoreProvider.class );
DB database = provider.getDatabase();
DBCollection collection = database.getCollection( "Associations" );
final BasicDBObject idObject = new BasicDBObject( 2 );
idObject.append( "Project_id", "projectID" );
idObject.append( "table", "Project_Module" );
BasicDBObject query = new BasicDBObject( 1 );
query.put( "_id", idObject );
BasicDBObject updater = new BasicDBObject( 1 );
updater.put( "$push", new BasicDBObject( "extraColumn", 1 ) );
collection.update( query, updater );
}