Fun With Errors

gistfile1.js

db.query(statement, function (err, res) {
  if (err) {
    throw new Error(err);
  } else {
    // Do normal stuff.
  }
});

db.query(statement, function (err, res) {
  if (err) {
    var originalMessage = err.message;
    err.message = [originalMessage, 'Query failed for some reason'];
    err.modelState = modelState; /* Pretend we already made an object called modelState
                                    that has useful data about the Model's state. */
    throw(err);
  } else {
    //do the rest of your stuff.
  }
});