This validator tests whether associated collection is going to be empty after saving. It will be passed if at least one association of the specified collection will exist. The validator provides helper method and default error message.

Limit your ActiveRecord models

AtomicArrays is a lightweight gem that aims to assist ActiveRecord with PostgreSQL array operations by offering a couple simple methods to update arrays in the database and the instance that it is called on. These methods are atomic in nature because they update the arrays in the database without relying on the current object's instantiated arrays.

first_or_create does not guarantee uniqueness by itself, and if there is a uniqueness constraint on the database, it may fail with a RecordNotUnique exception. This gem adds atomic_first_or_create, which, in conjunction with a uniqueness constraint, provides the correct behaviour.

Atomic update of JSON/JSONB fields for ActiveRecord models

Pub sub and websockets

Attach documents & files to Active Record models

Adds has_attachment (file store) properties to ActiveRecord. Supports local file, file-in-db, S3 and Cloudfiles backends.

A high performance ActiveRecord concern for Rails using the PostgreSQL array type.

Provides functionality to transparently store and retrieve encrypted attributes in ActiveRecord models.

Allows you to define CSV-style attributes for your ActiveRecord models

Generates attr_accessors that encrypt and decrypt attributes transparently

A method for restricting an attribute to a set of choices

Allow attribute-level read/write access control, per instance, of any ActiveModel class.

Allows step change for attributes.

Extends ActiveRecord attributes with a `:choices` pseudo-type that provides convenient methods for mapping each choice to its human readable form.

Add default attribute values when creating models.

AttributeDelegator provides a class method to ActiveRecord models that dynamically generates getter/setter to treat the attributes of a has_one model like native attributes. This is particularly useful because it allows the delegated attributes to be assigned via model.attributes= {}, such as by a form submission.

A model attribute enums plugin for Rails3. like 'symbolize' gem.

Builds macros to automatically manipulate your models' attributes.