Railroad-database problem

Hi all,

 I am facing with a new type of problem with railroad, explained

below

  1. I am using an oracle database in my application. In the database.yml
    file, I am having different schema connections to the same database.like

development:

database: real_database

username: schema_name1

password: ************

adapter: oracle

abcd_development:

database: real_database

username: schema_name2

password: ************

adapter: oracle

legacy_development:

database: real_database

username: schema_name3

password: **************

adapter: oracle

u can observe that only the usernames/schemas are different but the
database is the same for all the connections.

And according to the rails-database conventions when defining multiple
connections in database.yml, we have to create separate models for each
of the connections like

reporting.rb
class Reporting < ActiveRecord::Base

connection = “legacy_#{ENV[‘RAILS_ENV’]}”

establish_connection connection.to_sym

end

where ENV[‘RAILS_ENV’] is development. (configured)

and suppose that there is a table xyz under this schema (schema_name3),
then I have to inherit from this class and define the model for the xyz
table like

xyz.rb

class Xyz < Reporting

set_table_name ‘xyzs’

set_primary_key ‘xyz_id’

end

so whenever the xyz table is called, it automatically connects to the
legacy_development connection and proceeds. Right ??

This is the scenario. (Hope my understanding is proper…!@#$#)

  1.               Now I am trying to run the railroad under my
    

application having these database connections.

I think , what is happening is, the railroad is trying to find a table
named reportings , but Reporting is just the connecting model for the
legacy_development connection. The error which I am getting is

R09222:~/project1> railroad -M models

(eval):3:in `describe’: “DESC reportings” failed; does it exist?
(RuntimeError)

    from

/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/connection_adapters/oracle_adapter.rb:316:in
`columns’

    from

/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/base.rb:763:in
`columns’

    from

/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.15.3/lib/active_record/base.rb:782:in
`content_columns’

    from

/usr/local/lib/ruby/gems/1.8/gems/railroad-0.4.0/lib/railroad/models_diagram.rb:60:in
`process_class’

    from /usr/local

So It is clear that it is trying to find a table named reportings under
this schema.

When I exclude this file (reporting.rb), then itz giving another error
corresponding to the files inheriting the “Reporting” class like

railroad -M -e reporting.rb models

/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:266:in
`load_missing_constant’: uninitialized constant Reporting (NameError)

    from

/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:452:in
`const_missing’

    from

/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:464:in
`const_missing’

    from ./app/models/xyz.rb:1

    from

/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in
`gem_original_require’

How to make railroad understand that reporting.rb is not a table but
just a connection.

                    So how to solve this. Is the behaviour of

railroad is like this only or is there any alternative for this.

                    Please help me.



                    THNX in advance for the help.

Thanks and Regards,

S. Anand.

On 29 Nov 2007, at 10:48, Jazzy B. wrote:

reporting.rb
class Reporting < ActiveRecord::Base

connection = “legacy_#{ENV[‘RAILS_ENV’]}”

establish_connection connection.to_sym

end

[snip]

How to make railroad understand that reporting.rb is not a table but
just a connection.

I believe this is a pure rails problem. You need to set
self.abstract_class = true in the Reporting class so that rails knows
that there is no matching table.

Fred

Hi fred,
Thanks very much for the help… The problem is solved…

Regards,
Anand.