recurring_event | ruby library to aid in describing recurrent

Im trying to build an application with recurring events. In my database i have a table recurring_pattern:

I'm building a calendar app in Rails. It's possible to invite people to events. I'm having difficulties writing a query like @event.attending_users.

A calendar Event consists of one or many RecurringEvents. One RecurringEvent has one or many Attendees. The attendees tables is basically a join table that lists which users that's attending a RecurringEvent.

Event

I building a calender Rails app. It has Events, which can have one or more Recurring Events. E.g "Running every Monday, 100 times."

If a user deletes all of the recurring events, then I want the main Event also to be deleted.

In my RSpec test I do: delete recurring_events_path(@group, @recurring_event), but that yields DELETE "/groups/705777939/recurring_events.496

How should I craft the arguments to recurring_events_path so that it yields /groups/705777939/recurring_events/496?

routes.rb

I'm using Django 1.11, Postgresql 9.2, python 3.4

I want to select data based on table's column named event_type if event type is single then compare date that should be of same date (today's) date else select all dates of given (today's) date that type would be of recurring.

But can't we manage this using single query? Like we do CASE and WHEN, THEN in Aggregation? I tried using Q object but no luck. I want to check when value is 'single' then add condition, else another condition.

I could not find any good solution, currently I've achieved using this