The ActiveWarehouse library provides classes and functions which help with building Data Warehouses using Rails.

To install ActiveWarehouse, add the gem to your Gemfile:

gem 'activewarehouse'

ActiveWarehouse comes with several generators. In the examples below, you can use either example and the results will be the same.

Creates a SalesFact class and a sales_facts table.

script/generate fact Sales
script/generate fact sales

Creates a RegionDimension class and a region_dimension table.

script/generate dimension Region
script/generate dimension region

Creates a RegionalSalesCube class.

script/generate cube RegionalSales
script/generate cube regional_sales

Creates a CustomerHierarchyBridge class.

script/generate bridge CustomerHierarchy
script/generate bridge customer_hierarchy

Creates an OrderDateDimension class which is represented by a view on top of the DateDimension.

script/generate dimension_view OrderDate Date
script/generate dimension_view order_date date

The rules for naming are as follows:

Facts:

• Fact classes and tables follow the typical Rails rules: classes are singular and tables are pluralized.
• Both the class and table name are suffixed by "_fact".

Dimensions:

• Dimension classes and tables are both singular.
• Both the class name and the table name are suffixed by "_dimension".

Cube:

• Cube class is singular. If a cube table is created it will also be singular.

Bridge:

• Bridge classes and tables are both singular.
• Both the class name and the table name are suffixed by "_bridge".

Dimension View:

• Dimension View classes are singular. The underlying data structure is a view
• on top of an existing dimension.
• Both the class name and the view name are suffixed by "_dimension"

The ActiveWarehouse plugin does not directly handle Extract-Transform-Load processes, however the ActiveWarehouse ETL gem (installed separately) can help. To install it use:

gem install activewarehouse-etl

More information on the ETL process can be found at http://activewarehouse.rubyforge.org/etl