schema_migrations already exists error on db:migrate with two-database app

I have not yet created a unique unit-test for this issue, but I've started looking into it.

To recreate the problem, a part of the description which skimmed-over in the description above, I have these things going on in my rails app:

• The app connects to two databases, one as the natural rails database, and one read-only metadata database which is quite huge. Models for the metadata database inherit from an abstract class called Metadata:

class Metadata < ActiveRecord::Base

self.abstract_class = true

def self.database_name

metadata = "#{RAILS_ENV}_metadata"
configurations[metadata]['database']

end

def self.connect_to_metadata_database

metadata = "#{RAILS_ENV}_metadata"
@schema_prefix = Metadata.database_name + '.'
self.establish_connection metadata
    puts "Connected to #{metadata.inspect}"

end

connect_to_metadata_database

def self.table_name_prefix

@schema_prefix

end

end

• Also, in order to deal with another problem with allowing joins to occur across the two databases, I created an initializer file, which looks like this:

class ActiveRecord::Base
def self.set_schema_prefix

@@schema_prefix = configurations[RAILS_ENV]['database'] + '.'

end set_schema_prefix def self.table_name_prefix

@@schema_prefix

end end

class ActiveRecord::ConnectionAdapters::MysqlAdapter
def prefix_tables

self.tables.map{|t| @@schema_prefix + t}

end def self.set_schema_prefix

@@schema_prefix = ActiveRecord::Base.configurations[RAILS_ENV]['database'] + '.'

end set_schema_prefix end

code-formatting got messed up above, here's another try..

class Metadata < ActiveRecord::Base
  self.abstract_class = true
  def self.database_name
    metadata = "#{RAILS_ENV}_metadata"
    configurations[metadata]['database']
  end
  def self.connect_to_metadata_database
    metadata = "#{RAILS_ENV}_metadata"
    @schema_prefix = Metadata.database_name + '.'
    self.establish_connection metadata
        puts "Connected to #{metadata.inspect}"
  end
  connect_to_metadata_database
  def self.table_name_prefix
    @schema_prefix
  end
end

class ActiveRecord::Base
  def self.set_schema_prefix
    @@schema_prefix = configurations[RAILS_ENV]['database'] + '.'
  end
  set_schema_prefix
  def self.table_name_prefix
    @@schema_prefix
  end
end

class ActiveRecord::ConnectionAdapters::MysqlAdapter
  def prefix_tables
    self.tables.map{|t| @@schema_prefix + t}
  end
  def self.set_schema_prefix
    @@schema_prefix = ActiveRecord::Base.configurations[RAILS_ENV]['database'] + '.'
  end
  set_schema_prefix
end

I don't believe this problem exists in rails 3.0 from looking at the code itself, as stated in my original posting. This is a rails 2 issue only. If no work on rails 2 is going to occur, even the latest of the 2.x branches, then this issue can be closed.