# Odbc-rails gem installation problem

**URL:** <https://www.ruby-forum.com/t/odbc-rails-gem-installation-problem/121493>\
**Category:** Rails\
**Created:** [November 28, 2007, 1:27pm UTC](https://www.ruby-forum.com/t/odbc-rails-gem-installation-problem/121493 "2007-11-28T13:27:51Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![GPB](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/49beb7/32.png) [@GPB](https://www.ruby-forum.com/u/GPB)\
**Post date:** [November 28, 2007, 1:27pm UTC](https://www.ruby-forum.com/t/odbc-rails-gem-installation-problem/121493/1 "2007-11-28T13:27:51Z")

</div>

Hello…

I install the odbc-rails gem by running:

gem install -r odbc-rails --include-dependencies

Then I add require ‘odbc\_adapter’ to my config/environment.rb

When I start the server I get this beauty…

C:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.5/lib/active\_record/  
connection\_adapters/abstract/connection\_specification.rb:34:  
uninitialized class variable @@allow\_concurrency in ActiveRecord::Base  
(NameError)

```
    from C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:

```

27:in `gem\_original\_require’

```
    from C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:

```

27:in `require’

```
    from C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.4/lib/

```

active\_support/dependencies.rb:495:in `require’

```
    from C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.4/lib/

```

active\_support/dependencies.rb:342:in `new\_constants\_in’

```
    from C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.4/lib/

```

active\_support/dependencies.rb:495:in `require’

```
    from C:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.5/lib/

```

active\_record/connection\_adapters/abstract\_adapter.rb:10

```
    from C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:

```

27:in `gem\_original\_require’

```
    from C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:

```

27:in `require’

```
     ... 27 levels...

    from C:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.5/lib/commands/

```

server.rb:39

```
    from C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:

```

27:in `gem\_original\_require’

```
    from C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:

```

27:in `require’

```
    from script/server:3

```

Appreciate anyones help.

Thanks,

GPB