activerecord-jdbc-adapter is a database adapter for Rails’ ActiveRecord component that can be used with JRuby[http://www.jruby.org/]. It allows use of virtually any JDBC-compliant database with your JRuby on Rails application.
Activerecord-jdbc-adapter provides full or nearly full support for: MySQL, PostgreSQL, SQLite3, Oracle, Microsoft SQL Server, DB2, FireBird, Derby, HSQLDB, H2, and Informix.
Other databases will require testing and likely a custom configuration module. Please join the activerecord-jdbc mailing-lists[http://kenai.com/projects/activerecord-jdbc/lists] to help us discover support for more databases.
== Using ActiveRecord JDBC
=== Inside Rails
To use activerecord-jdbc-adapter with JRuby on Rails:
Choose the adapter you wish to gem install. The following pre-packaged adapters are available:
- base jdbc (activerecord-jdbc-adapter). Supports all available databases via JDBC, but requires you to download and manually install the database vendor’s JDBC driver .jar file.
- mysql (activerecord-jdbcmysql-adapter)
- postgresql (activerecord-jdbcpostgresql-adapter)
- sqlite3 (activerecord-jdbcsqlite3-adapter)
- derby (activerecord-jdbcderby-adapter)
- hsqldb (activerecord-jdbchsqldb-adapter)
- h2 (activerecord-jdbch2-adapter)
- mssql (activerecord-jdbcmssql-adapter)
2a. For Rails 3, if you’re generating a new application, use the following command to generate your application:
jruby -S rails new sweetapp -m http://jruby.org/rails3.rb
2b. Otherwise, you’ll need to perform some extra configuration steps to prepare your Rails application for JDBC.
If you’re using Rails 3, 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' gem 'jdbc-sqlite3' else gem 'sqlite3-ruby', :require => 'sqlite3' end
If you’re using Rails 2:
jruby script/generate jdbc
- 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.
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
For JNDI data sources, you may simply specify the JNDI location as follows (the adapter will be automatically detected):
production: adapter: jdbc jndi: jdbc/mysqldb
If you’re really old school you might want to use ARJDBC with a DB2 on z/OS.
development: adapter: jdbc encoding: unicode url: jdbc:db2j:net://mightyzoshost:446/RAILS_DBT1 driver: com.ibm.db2.jcc.DB2Driver schema: DB2XB12 database: RAILS_DB1 tablespace: TSDE911 lob_tablespaces: first_table: TSDE912 username: scott password: lion
=== Standalone, with ActiveRecord
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
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' )
== Extending AR-JDBC
You can create your own extension to AR-JDBC for a JDBC-based database that core AR-JDBC does not support. We’ve created an example project for the Intersystems Cache database that you can examine as a template. See the project for more information at the following URL:
== Getting the source
The source for activerecord-jdbc-adapter is available using git.
git clone git://github.com/nicksieger/activerecord-jdbc-adapter.git
Please file bug reports at http://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.
== Project Info
- Mailing Lists: http://kenai.com/projects/activerecord-jdbc/lists
- Issues: http://kenai.com/jira/browse/ACTIVERECORD_JDBC
- Source: git://github.com/nicksieger/activerecord-jdbc-adapter.git git://kenai.com/activerecord-jdbc~main
== 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. You alse need to grant “blog” create privileges on ‘test_rake_db_create.*’.
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:
== 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
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.