model.id is not being added to a collection._byId hash table

[jmoretti]

After digging into the problem of why I wasn't able to get a model from a collection using the Backbone.Collection.get() method, I discovered that the reason for this was because models are being added to the collection by pushing them directly into the Backbone.Collection.models array bypassing the Backbone.Collection.add() method which is where Backbone.Collection._byId is maintained. I can fix this by simply using the Backbone.Collection.push() method, but I noticed you had a comment directly above this snippet of code:

// do not use Collection methods!

The exclamation point means this must be serious...

Of course I can work around it by modifying it like so:

// do not use Collection methods!
var len = 0;
if (!opts.add) {
   collection.models = [];
}
var modelToBeAdded = [];
while (row = rows.nextRow()) {
   var m = collection.map_row(collection.model, row);
   if (m) {
      collection._byId[m.id] = m;
      collection.models.push(m);
      ++len;
   }
}

Out of curiosity, why don't we use the Backbone.Collection methods?