lookup_table

Database fed lookup table.

This gem allows to quickly set up a look up table with content stored in the database. The library supports two modes of operation: preload the whole table into a lookup hash or lookup (and cache) values on demand.

The gem is useful for implementing data processing algorithms where some functions are given as table based mappings, such as implementing statistical models. The main purpose of the gem is making the code using such database backed lookup more readable.

Usage

Assuming a table "deprivation" contains a mapping from zip codes to deprivation, a lookup table can be constructed with:

Gemfile:

gem "lookup_table"

hello.rb:

require "lookup_table"

ZipcodeToDeprivation = LookupTable.create "deprivation", :zip_code, :deprivation

deprivation = ZipcodeToDeprivation[ "7777AA" ]

More features are described in the spec.