This gem provides support for using Sequel as an ORM for Rails applications by providing features that are similar to ActiveRecord's integration with Rails. It is an alternative to sequel-rails.

Add this line to your application's Gemfile:

gem 'sequelize-rails'

And then execute:

$ bundle install

If you are looking to replace ActiveRecord entirely, you may need to either generate your Rails app using --skip-active-record or manually remove references to ActiveRecord in your Gemfile, config/application.rb, and config/environments/*.rb files.

Database Management

• Connectivity via config/database.yml
• Console via rails db
• Migrations via Sequel::Migration
• Migration Generators via rails generate migration (not supported yet)
• Rake tasks via rails db:*

Test Suite

• Minitest Helpers

Rake Helpers

• Does not connect to the primary database in Rake (tasks by default)
• Allows for explicit connection to the primary database by invoking db:connection

This gem will automatically use your application's config/database.yml file to configure the available database connection(s).

A connection to the "primary" database is automatically established when the application is loaded. This connection will by used by default for all model classes that do not specify a different connection.

The primary connection can be referenced directly via:

Sequel::DATABASES.first # instead of ActiveRecord::Base.connection

A common convention within applications that use Sequel is to store the primary connection in the DB constant, which can be easily done within an initializer file via the following:

# config/initializers/sequel.rb
DB = Sequel::DATABASES.first unless defined?(DB)

Additional connections can be configured in your config/database.yml file by adding additional entries to the databases key. For example:

# config/database.yml

# ... snip ...

production:
  <<: *default
  database: <%= ENV["DATABASE_URL"] %>

my_replica:
  <<: *default
  database: <%= ENV["REPLICA_DATABASE_URL"] %>

Additional connections can be retrieved via Sequel::Rails.connect_to, such as within the example below:

replica_connection = Sequel::Rails.connect_to :my_replica

By default, this gem will not connect to the primary database when running Rake tasks. This is to prevent Rake tasks from accidentally depending on a database connection when one is not necessary. If you would like to connect to the primary database within a Rake task, you can do so by invoking the db:connection task, or by calling Sequel::Rails.connect_to :primary from within your task.

# Rakefile

# no database connections are initialized by default
task :no_db_connection do
  Sequel::DATABASES # => []
  Sequel::DATABASES.length # => 0
end

# connects to the primary database explicitly
task :my_task do
  db = Sequel::Rails.connect_to :primary
  Sequel::DATABASES # => [db]
  Sequel::DATABASES.length # => 1
end

# connects to the primary database via the db:connection task
task :my_other_task => "db:connection" do
  Sequel::DATABASES # => [<primary db connection here>]
  Sequel::DATABASES.length # => 1
end

You can connect directly to your database via the rails db command. This command is similar to the rails console command, but instead of loading your application, it will connect directly to the database.

# connects to the primary database
$ rails db

# connects to the database of the test environment
$ rails db -e test

Please note that only the -e flag is supported at this time. Other flags such as --database are not supported.

This gem provides support for using Sequel's migration system. Migrations are stored in the db/migrate directory and can be executed via the rails db:migrate command.

More information about Sequel's migration system can be found in the Sequel documentation.

Rails supports the generation of migrations via the rails generate migration command. This gem does not currently support this feature, but pull requests are welcome.

This gem provides a set of rake tasks that are similar to the ActiveRecord tasks. These tasks can be used to create, drop, migrate, and seed your database.

This helper can be used to assert that a specific number of database queries are executed within the given block of code.

Example:

# asserts that exactly 2 queries are executed
assert_num_queries(2) do
  u = User[id: 1234]
  u.update(name: "Random User")
end

# asserts that 0 queries are executed
assert_num_queries(0) do
  some_hopefully_cached_method
end

# asserts that 1 to 3 queries are executed
assert_num_queries(1..3) do
  u = User.find_or_create(name: "Random User")
end

# asserts that at least 3 queries are executed
assert_num_queries(3..) do
  stuff_here
end

# asserts that no more than 2 queries are executed
assert_num_queries(..2) do
  other_stuff_here
end

This helper can be used to assert that no database queries are executed within the given block of code.

Example:

# asserts that no queries are executed
assert_no_queries do
  some_hopefully_cached_method
end

Bug reports and pull requests are welcome on GitHub at https://github.com/kenaniah/sequelize-rails.

This repository contains a handful of commands that can be used to facilitate this gem's development. These are:

The gem is available as open source under the terms of the MIT License.

• Support rails console --sandbox (auto rollback all transactions)
• Support logging
• Support db rake tasks
• Support reloading (disconnect all connections)
• Support ActiveRecord plugins / conventions (shims)
• Support PostgreSQL custom format for dump & restore
• Support generators (including orm)
• Support migration generator (and parsed attributes)