code: function onWrite(req) {
    if(!this.transaction || !this.watched || req.conn.id === this.id) {
      return false;
    }
  
    //console.dir(req.keys);
    //console.dir(req.args);
  
    var keys = req.keys || req.def.getKeys(req.args), i, key;
    for(i = 0;i < keys.length;i++) {
      key = '' + keys[i];
      //console.error('got change with key %s', key);
      //console.error('got change with value %s', value);
      //console.error('got change with conn id %j', req.conn.id);
      if(~this.watched.indexOf(key)) {
        //console.error('setting conflict on %s', keys[i]);
        //console.error('setting conflict from %s', req.conn.id);
        this.transaction.conflict = true;
        return true;
      }
    }
  }
docs: Listener for write events emitted by the database.
  
  Inspects the request object and if the request keys
  match any keys being watched by this connection and
  the request was from another connection then a conflict
  if flagged on a transaction if a transaction exists.