Satya's blog - JRuby on Rails with Sybase

Sep 30 2009 10:39 JRuby on Rails with Sybase [link] [comment]

Got Sybase*? Got Rails? You're skewered. But you can do it with JRuby and jTDS. Assuming Ubuntu 9.04, but any deb-based system should do.
*(or MSSQL, or SQLServer, whatever the heck it's called)

Get jruby1.1 (or whatever the latest is). This also might drag in 90+ other dependencies. You don't have a choice. Get libjtds-java. Get the following gems: activerecord-jdbc-adapter jruby-openssl 

sudo apt-get install jruby1.1 libjtds-java
sudo jruby -S gem install rails activerecord-jdbc-adapter jruby-openssl

jruby -S: installs the gems into the jruby system instead of the ruby (or cruby, for C) system.

Start a jrails (my term for JRuby on Rails) app by doing: jruby -S rails jdbctestapp

Edit config/database.yml to read something like: 

development:
  adapter: jdbc
  url: jdbc:jtds:sybase://server:4100/;TDS=5.0
  database: mydatabasename
  username: foo
  password: bar
  driver: net.sourceforge.jtds.jdbc.Driver

Assuming you know how to handle the database.yml file. For MSSQL, change 'sybase' to 'sqlserver' and set TDS=8.0 (or remove the TDS thing altogether, including the semi-colon).

And then, the best-kept secret of the internet: Add this line, or similar, to your environment.rb file: 

require '/usr/share/java/jtds.jar'

That's right, the full path to the jtds jar file (you can find it with dpkg -L libjtds-java|grep jar).

Tag: rails

Comments:
  • Sat Oct 10 20:21:19 2009 Gresh wrote:
    I've tried using JRuby/Rails with Sybase jConnect and jTds, however it seems migrations are not supported. Initially I get this error:

    ActiveRecord::ActiveRecordError: 600 is the maximum allowable size of an index. Composite index specified is 2048 bytes.
    : CREATE UNIQUE INDEX [rn_a_unique_schema_migrations] ON rn_a_schema_migrations ([version])

    And there then seems to be problems with sequences:

    ActiveRecord::ActiveRecordError: Incorrect syntax near the keyword 'IDENTITY'.
    : CREATE TABLE rn_a_users ([id] int NOT NULL IDENTITY(1, 1) PRIMARY KEY, [username] varchar(2048), [first_name] varchar(2048), [last_name] varchar(2048), [active] bit, [password] varchar(2048), [salt] varchar(2048), [email] varchar(2048), [created_at] datetime, [updated_at] datetime)

    I will try creating the schema I need manually, hopefully rails will work against it.

    Also on ASIQ it seems we cannot pick up the list of tables, so even with an existing schema, things fail. I haven't tried yet with jTds.
  • Sat Oct 10 23:29:39 2009 Satya wrote:
    I don't know jack about the sybase stuff. I just need it to work with what we have at work. I wish Rails supported Sybase better. Supposedly there is an activerecord-sybase-adapter which is not gem-installable. I have not found it.
More: