Databases

Amalgalite embeds the SQLite database engine as a ruby extension. There is no need to install SQLite separately.

Correios CEP gem finds updated Brazilian addresses by zipcode, directly from Correios database. No HTML parsers.

This gem provides an easy way of storing and retrieving encryption keys in the database.

SchemaValidations extends ActiveRecord to automatically create validations by inspecting the database schema. This makes your models more DRY as you no longer need to duplicate NOT NULL, unique, numeric and varchar constraints on the model level.

Rein adds bunch of methods to your ActiveRecord migrations so you can easily tame your database.

Strategies for cleaning databases using Sequel. Can be used to ensure a clean state for testing.

Rails port of Heroku PG Extras. The goal of this project is to provide a powerful insights into PostgreSQL database for Ruby on Rails apps that are not using the default Heroku PostgreSQL plugin.

A Ruby database driver for ClickHouse (also Clickhouse CLI and web GUI included)

Comprehensive import/export tools between Excel/CSV & ActiveRecord Databases, Rails apps, and any Ruby project.

A gem for interacting with the GeoIP2 webservices and databases. MaxMind provides geolocation data as downloadable databases as well as through a webservice.

Another Logger - Addon for Database Support (LogDb, Log Model etc.)

It just makes sense to store mutable, site-wide, admin-level settings in the database. Right? A key-value table may be more flexible, but maybe we don't want to be flexible! If you truly want that flexibility: http://github.com/stephencelis/kvc

Anonymise the data in your database.

Provide an easy way to check the consistency of the database constraints with the application validations.

Seed Fu is an attempt to once and for all solve the problem of inserting and maintaining seed data in a database. It uses a variety of techniques gathered from various places around the web and combines them to create what is hopefully the most robust seed data system around.

Guard::Migrate automatically runs your database migrations when needed

props-activerecord - Manage Setting Hierachies Addon for Database Support (ConfDb, Props Model, etc.)

Rails database query counter that stays out of your way

Ensures consistent output of db/schema.rb despite local differences in the database

Provides a simple and intuitive interface for the Movie Database API making use of OpenStruct.

Strategies for cleaning databases using Mongoid. Can be used to ensure a clean state for testing.

Astrails-Safe is a simple tool to backup databases (MySQL and PostgreSQL), Subversion repositories (with svndump) and just files. Backups can be stored locally or remotely and can be enctypted. Remote storage is supported on Amazon S3, Rackspace Cloud Files, or just plain FTP/SFTP.

This gem enables your model to query the database using the earthdistance extension. This should be much faster than using trigonometry functions over standart indexs.

This gem provides the Rails 3 with database adapter for AWS RedShift.

Persistent event repository implementation for RubyEventStore based on ActiveRecord. Ships with database schema and migrations suitable for PostgreSQL, MySQL ans SQLite database engines. Includes repository implementation with linearized writes to achieve log-like properties of streams on top of SQL database engine.

A call to the ipinfodb.com will be done to retreive the geolocation based on the IP address. No need to include a database file in the application.

Allows Sequel to use ActiveRecord connection for database interaction.

The plutus plugin provides a complete double entry accounting system for use in any Ruby on Rails application. The plugin follows general Double Entry Bookkeeping practices. All calculations are done using BigDecimal in order to prevent floating point rounding errors. The plugin requires a decimal type on your database as well.

Use database lookup tables in AR models.

This Ruby extension implements a DataMatrix encoder for Ruby. It is typically used to create semacodes, which are barcodes, that contain URLs. This encoder does not create image files or visual representations of the semacode. This is because it can be used for more than creating images, such as rendering semacodes to HTML, SVG, PDF or even stored in a database or file for later use. Ruby 1.9 compatibility added by Tore Darell <toredarell@gmail.com>.

Ruby port of Heroku PG Extras. The goal of this project is to provide a powerful insights into PostgreSQL database for Ruby on Rails apps that are not using the default Heroku PostgreSQL plugin.

Mongify allows you to map your sql data into a mongodb document database with a simple DSL.

Obtain ActiveRecord results with a custom ordering with no need to store anything in the database.

A gem providing support for table partitioning in ActiveRecord. Support is available for postgres and AWS RedShift databases. Other features include child table management (creation and deletion) and bulk data creating and updating.

A Rails engine that adds a piece of middleware to the top of your middleware stack that looks for redirect rules stored in your database and redirects you accordingly.

A pure Ruby interface to the WordNet database

A library for reading Microsoft Access databases

Yandex ClickHouse database interface for Ruby

A Rails library for storing user sessions in a backend database

Multiple databases for Rails

Ambry is not an ORM, man! It's a database and ORM replacement for (mostly) static models and small datasets. It provides ActiveModel compatibility, and flexible searching and storage.

Add support for master/slave database database clusters in ActiveRecord to improve performance.

Provides a wrapper for the UNIX-style Database Manager Library

The appengine gem is a set of classes, plugins, and tools for integration with Google App Engine. It provides access to the App Engine runtime environment, including logging to the Google Cloud Console and interrogation of hosting properties. It also provides Rake tasks for managing your App Engine application, for example to run production maintenance commands such as database migrations. This gem is NOT required to deploy your Ruby application to App Engine.

Creates stub classes from any ActiveRecord model. By using stubs in your tests you don't need to load Rails or the database, sometimes resulting in a 10x speed improvement. ActiveMocker analyzes the methods and database columns to generate a Ruby class file. The stub file can be run standalone and comes included with many useful parts of ActiveRecord. Stubbed out methods contain their original argument signatures or ActiveMocker friendly code can be brought over in its entirety. Mocks are regenerated when the schema is modified so your mocks won't go stale, preventing the case where your unit tests pass but production code fails.

SecondBase provides support for Rails to manage dual databases by extending ActiveRecord tasks that create, migrate, and test your databases.

Creating CSV files in Ruby is painful! CSV Shaper makes life easier! It's ideal for converting database backed models with attributes into CSV output. It can be used without Rails, but works great with ActiveRecord models and even comes with support for it's own template handling.

RubyMotion wrapper for NanoStore, a lightweight schema-less key-value document database based on sqlite.

SQLite/Ruby is a module to allow Ruby scripts to interface with a SQLite database.

Declarative API for specifying features, switchable in declaration, database and cookies.