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.

== Project Info

* Mailing Lists: http://kenai.com/projects/activerecord-jdbc/lists
* Issues: http://kenai.com/jira/browse/ACTIVERECORD_JDBC
* Source: git://kenai.com/activerecord-jdbc~main
git://github.com/nicksieger/activerecord-jdbc-adapter.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[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:

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 http://jruby.org/rails3.rb

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
else
gem sqlite3-ruby', :require => 'sqlite3'
end

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'
end

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.

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 database type
using the adapter key and the JNDI location as follows:

production:
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:

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
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.

== 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
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 <[email protected]> and Ola Bini
<[email protected]> 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.