I kept getting the error, "undefined method 'each'" when working on the results from the following code:
channels = Channel.find_by_network_id(network_id)
It turns out that the statement was returning a structure of one channel, NOT a collection containing one channel structure.
This meant that I'd get the above error if I tried to iterate through the expected "collection" of 1 or more channels. It wasn't a collection and, therefore, didn't have an 'each' method.
After looking here for the answer, I figured out that using the following code always brought back a collection, regardless of how many records matched the criteria:
channels = Channel.find_all_by_network_id(network_id)
Hope this helps someone down the road. Let me know if there's a more elegant (or acceptable) way of doing this.