Warning when creating node with no terms and sorting view by similarity weight

Issue Summary

When creating a node with no taxonomy terms selected, similarnodes (or views) throws a user warning when you sort the view by 'Similarnodes: weight':

user warning: Unknown column 'similarnodes_similar_weight' in 'order clause' query: SELECT node.nid, node.created AS node_created_created, node.title AS node_title, node.changed AS node_changed FROM node node LEFT JOIN i18n_node i18n ON node.nid = i18n.nid WHERE (i18n.language ='en' OR i18n.language ='' OR i18n.language IS NULL) AND ( (node.status = '1') AND (1 = 0) ) ORDER BY node_created_created DESC, similarnodes_similar_weight ASC LIMIT 0, 5 in /includes/database.mysql.inc on line 172.