Paginate entries by arbitrary cycle in Rails

Question

I have a model:

entry (created_at: datetime, temperature: float, melt_type: string)

I need to paginate entries by cycle (rather than a set number of entries).

A cycle is defined by the first entry with any melt_type value to the last entry before another melt_type is entered. (melt_type appears for a few days at the beginning of a cycle lasting ~40 days, but won't appear any other time in a cycle).

I've found a few pagination gems (will_paginate or Kaminari), but am having difficulty finding a solution that doesn't use an exact number of entries per page.

Do you want to set the entries per page using `will_paginate`? — Pavan, Jun 22 '14 at 18:39
Not necessarily. It just seemed well supported, but I could go with a different solution. — Charlie Triplett, Jun 22 '14 at 19:34
kaminari seems closer to what I need https://github.com/amatsuda/kaminari/wiki/Kaminari-recipes#-how-do-i-paginate-an-array — Charlie Triplett, Jun 22 '14 at 23:01
melt_type indicates the beginning of a new cycle. melt_type entries will occur for the first ~8 days per cycle, but not in the middle of cycles. — Charlie Triplett, Jun 23 '14 at 18:56

score 0 · Accepted Answer · answered Jun 26 '14 at 23:57

I was thinking of this the wrong way.

What I really needed was to create a single table inheritance in which I created a new model called melt_cycle that inherits from entries instead of the ActiveRecord::Base.

It does require the user to designate the beginning of the melt_cycle, but that's not unreasonable.

Now I just need to figure out how to automatically assign entries to ID of the previous melt_cycle_start

Now my entry model looks like (created_at: datetime, temperature: float, melt_type: string, melt_cycle_start: boolean)

Here's a great tutorial from Team Treehouse on Single Table Inheritance: http://teamtreehouse.com/library/rails-models/migrations-and-relationships/single-table-inheritance

Paginate entries by arbitrary cycle in Rails

1 Answers1