query-based to many relationship

gistfile1.js

  messages: SC.RecordAttribute.create({
    toType: function(record, key, value) {
      var ary = record._messages ;
      if (!ary) {
        console.log('creating a messages query for Mailbox[%@]'.fmt(record.get('guid')));
        CoreOI.Record.messages++ ;
        ary = record._messages = record.get('store').findAll(SC.Query.create({
          recordType: 'CoreOI.Message',
          conditions: "mailbox = %@",
          parameters: [record],
          orderBy: "dateSent DESC"
        }));
      } else {
        console.log('verifying freshness of messages query for Mailbox[%@]'.fmt(record.get('guid')));
        ary.refresh() ;
      }
      return ary ;
    }
  }),