ArAggregateByInterval

---

Build arrays of counts, sums and averages from Ruby on Rails ActiveRecord models grouped by days, weeks or months. e.g.:

# default 'group by' is 'created_at'
Blog.count_weekly(1.month.ago).values
=> [4, 2, 2, 0]

Why?

1. to simplify "group by" SQL queries when weeks or months are involved
2. to fill in 0's for days/weeks/months where database has no data

Usage

ActiveRecordModel.{sum,count,avg}_{daily,weekly,monthly}(arg_hash).{values,values_and_dates}

#values //(returns an array of numerics)
=> [4, 2, 15, 0, 10]

#values_and_dates //(returns an array of hashes)
=> [{date: DateObject, value: 0}, {date: DateObject, value: 5}]

Examples

Total blog posts created weekly

Blog.count_weekly({
  group_by_column: :created_at,
  from: 6.months.ago,
  to: Time.zone.now
}).values

Total calories burned per week

Exercise.sum_weekly({
  group_by_column: :created_at,
  aggregate_column: :calories,
  from: 6.months.ago,
  to: Time.zone.now
}).values

Weekly revenue since beginning of year (with dates)

Billing.sum_weekly({
  group_by_column: :transacted_at,
  aggregate_column: :cents, # necessary when using sum as opposed to count
  from: Time.zone.now.beginning_of_year,
  to: Time.zone.now
}).values_and_dates