OlapReport

Olap-like queries & aggregations for activerecord models using defined hierarchies & measures

Installation

Add this line to your application's Gemfile:

gem 'olap_report'

And then execute:

$ bundle

Or install it yourself as:

$ gem install olap_report

Usage

Define dimensions, measures & aggregations (if needed) in your ActiveRecord model.

class Fact < ActiveRecord::Base
  # include OlapReport::Cube module to your ActiveRecord model
  include OlapReport::Cube

  belongs_to :user

  # define dimensions for your model
  # define_dimension <dimension name> do |d|
  define_dimension :user do
    level :user_id
    level :group_id, joins: :user
    level :category, joins: {user: :group}
  end

  define_dimension :date do
    # define layers by date periods
    # dates <column name>, by: <Array of periods (:minute, :hour, :day, :week, :month, :year)>
    dates :created_at, by: [:day, :week, :month, :quoter, :year]
  end

  # define_measure <measure name>, <function name, :sum by default>, hash of options
  define_measure :score_avg, :avg, column: :score
  define_measure :score_sum, :sum, column: :score
  define_measure :score_count, :count, column: :score

  # define table aggregations if needed
  # define_aggregation <dimension name> => <level name>
  define_aggregation user: :category
  define_aggregation user: :group_id, date: :month
end

Use #projection method of your model class to calculate summaries by levels

Fact.slice(dimensions: {<dimension name> => <level name>, ...}, measures: [<measure name>, <measure_name>, ...])

Use # aggregate! method of your model class to create aggregation tables for defined aggregations

Fact.aggregate!

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request