README.txt

Path: README.txt
Last Update: Tue Jun 29 11:58:01 +0000 2010

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

Databases

What‘s there, and what is not there:

  • MySQL - Complete support
  • PostgreSQL - Complete support
  • Oracle - Complete support
  • Microsoft SQL Server - Complete support except for change_column_default
  • 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>)
  * derby (<tt>activerecord-jdbcderby-adapter</tt>)
  * hsqldb (<tt>activerecord-jdbchsqldb-adapter</tt>)
  * h2 (<tt>activerecord-jdbch2-adapter</tt>)
  * sqlite3 (<tt>activerecord-jdbcsqlite3-adapter</tt>)
  1. Run the "jdbc" generator to prepare your Rails application for JDBC.
     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 un 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 Rails::Initializer. (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'
     end
    
  2. 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 databas adapter name as below.

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

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

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

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:
     ActiveRecord::Base.establish_connection(
       :adapter => 'jdbcderby',
       :database => "db/my-database"
     )
    

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

     ActiveRecord::Base.establish_connection(
       :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://github.com/nicksieger/activerecord-jdbc-adapter.git

Feedback

Please file bug reports at kenai.com/jira/browse/ACTIVERECORD_JDBC. 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 jruby -S rake to run the tests. A database named weblog_development 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 weblog_development and a user named "blog" and an empty password.

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 <nick@nicksieger.com> and Ola Bini <olabini@gmail.com> 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.

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