Skip to content


Subversion checkout URL

You can clone with
Download ZIP
ActiveRecord adapter for JDBC and JRuby.
Ruby Java Shell
Fetching latest commit...
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.


activerecord-jdbc-adapter is a database adapter for Rails' ActiveRecord
component that can be used with JRuby[]. It allows use of
virtually any JDBC-compliant database with your JRuby on Rails application.

== Project Info

* Mailing Lists:
* Issues:
* Source: git:// 

== Databases

What's there, and what is not there:

* MySQL - Complete support
* PostgreSQL - Complete support
* Oracle - Complete support
* Microsoft SQL Server - Complete support
* DB2 - Complete, except for the migrations:
  * change_column 
  * change_column_default
  * remove_column
  * rename_column
  * add_index
  * remove_index
  * rename_table
* FireBird - Complete, except for change_column_default and rename_column
* Derby - Complete, except for:
  * change_column
  * change_column_default
  * remove_column
  * rename_column
* HSQLDB - Complete
* H2 - Complete
* SQLite3 - work in progress
* Informix - Fairly complete support, all tests pass and migrations appear to work.  Comments welcome.

Other databases will require testing and likely a custom configuration module.
Please join the activerecord-jdbc
mailing-lists[] to help us discover
support for more databases.

== Using ActiveRecord JDBC

=== Inside Rails

To use activerecord-jdbc-adapter with JRuby on Rails:

1. Choose the adapter you wish to gem install. The following pre-packaged
   adapters are available:

  * base jdbc (<tt>activerecord-jdbc-adapter</tt>). Supports all available databases via JDBC, but requires you to download and manually install the database vendor's JDBC driver .jar file.
  * mysql (<tt>activerecord-jdbcmysql-adapter</tt>)
  * postgresql (<tt>activerecord-jdbcpostgresql-adapter</tt>)
  * sqlite3 (<tt>activerecord-jdbcsqlite3-adapter</tt>)
  * derby (<tt>activerecord-jdbcderby-adapter</tt>)
  * hsqldb (<tt>activerecord-jdbchsqldb-adapter</tt>)
  * h2 (<tt>activerecord-jdbch2-adapter</tt>)
  * mssql (<tt>activerecord-jdbcmssql-adapter</tt>)

2a. For Rails 3, if you're generating a new application, use the
    following command to generate your application:

   jruby -S rails myapp -m

2b. Otherwise, you'll need to run the "jdbc" generator to prepare your
    Rails application for JDBC.

   If you're using Rails 3, first you'll need to modify your Gemfile
   to use the activerecord-jdbc-adapter gem under JRuby. Change your
   Gemfile to look like the following (using sqlite3 as an example):

    if defined?(JRUBY_VERSION)
      gem 'activerecord-jdbc-adapter', :require => false
      gem 'jdbc-sqlite3, :require => false
      gem sqlite3-ruby', :require => 'sqlite3'

   Next, run the generator. With Rails 3:

    jruby script/rails generate jdbc

   With Rails 2:

    jruby script/generate jdbc
   The initializer and rake task files generated are guarded such that
   they won't be loaded if you still run your application under C Ruby.

   Legacy: If you're using Rails prior to version 2.0, you'll need to
   add one-time setup to your config/environment.rb file in your Rails
   application. Add the following lines just before the
   <code>Rails::Initializer</code>. (If you're using
   activerecord-jdbc-adapter under the old gem name used in versions
   0.5 and earlier (ActiveRecord-JDBC), replace
   'activerecord-jdbc-adapter' with 'ActiveRecord-JDBC' below.)

    if RUBY_PLATFORM =~ /java/
      require 'rubygems'
      gem 'activerecord-jdbc-adapter'
      require 'jdbc_adapter'

3. Configure your database.yml in the normal Rails style. 

   Legacy configuration: If you use one of the convenience
   'activerecord-jdbcXXX-adapter' adapters, you can still put a 'jdbc'
   prefix in front of the database adapter name as below.

      adapter: jdbcmysql
      username: blog
      hostname: localhost
      database: weblog_development

   For other databases, you'll need to know the database driver class
   and URL. Example:

      adapter: jdbc
      username: blog
      driver: com.mysql.jdbc.Driver
      url: jdbc:mysql://localhost:3306/weblog_development

   For JNDI data sources, you may simply specify the database type
   using the adapter key and the JNDI location as follows:

      adapter: mysql
      jndi: jdbc/mysqldb

=== Standalone, with ActiveRecord

1. Install the gem with JRuby:

    jruby -S gem install activerecord-jdbc-adapter

   If you wish to use the adapter for a specific database, you can install it
   directly and a driver gem will be installed as well:

    jruby -S gem install activerecord-jdbcderby-adapter

2. If using ActiveRecord 2.0 (Rails 2.0) or greater, you can skip to the next
   step. Otherwise, ensure the following code gets executed in your script:

    require 'rubygems'
    gem 'activerecord-jdbc-adapter'
    require 'jdbc_adapter'
    require 'active_record'

3. After this you can establish a JDBC connection like this:

      :adapter => 'jdbcderby',
      :database => "db/my-database"

   or like this (but requires that you manually put the driver jar on the classpath):

      :adapter => 'jdbc',
      :driver => 'org.apache.derby.jdbc.EmbeddedDriver',
      :url => 'jdbc:derby:test_ar;create=true'

== Getting the source

The source for activerecord-jdbc-adapter is available using git.

  git clone git://

== Feedback

Please file bug reports at If you're not sure if
something's a bug, feel free to pre-report it on the mailing lists.

== Running AR-JDBC's Tests

Drivers for 6 open-source databases are included. Provided you have MySQL
installed, you can simply type <tt>jruby -S rake</tt> to run the tests. A
database named <tt>weblog_development</tt> is needed beforehand with a
connection user of "blog" and an empty password.

If you also have PostgreSQL available, those tests will be run if the
`psql' executable can be found. Also ensure you have a database named
<tt>weblog_development</tt> and a user named "blog" and an empty

If you want rails logging enabled during these test runs you can edit 
test/jdbc_common.rb and add the following line:

require 'db/logger'

== Running AR Tests

To run the current AR-JDBC sources with ActiveRecord, just use the
included "rails:test" task. Be sure to specify a driver and a path to
the ActiveRecord sources.

  jruby -S rake rails:test DRIVER=mysql RAILS=/path/activerecord_source_dir

== Authors

This project was written by Nick Sieger <> and Ola Bini
<> with lots of help from the JRuby community.

== License

activerecord-jdbc-adapter is released under a BSD license. See the LICENSE file
included with the distribution for details.

Open-source driver gems for activerecord-jdbc-adapter are licensed under the
same license the database's drivers are licensed. See each driver gem's
LICENSE.txt file for details.
Something went wrong with that request. Please try again.