From: "R. Mark Volkmann" <mark@...>
Date: 2005-04-02T12:21:37+09:00
Subject: Re: gems for DBI and MySQL?

Quoting Kirk Haines <khaines@enigo.com>:

> R. Mark Volkmann wrote:
>
> > Does Rails use DBI to access databases?
>
> No.
>
> > Does Rails support MySQL out of the box?
> > I'm not writing a web app.  However, if the answer to both questions above
> > is "yes" then it would seem that the easiest way to get myself setup to
> > use MySQL
> > would be to install Rails.  True?
>
> No.
>
> It's easy to just do it by hand.
>
> Get mysql-ruby (http://tmtm.org/en/mysql/ruby/README.html), which is the C
> interface, or ruby-mysql (http://tmtm.org/en/ruby/mysql/README_en.html),
> which is the pure Ruby interface.  Follow the easy instructions to build
> this.
>
> Download DBI (http://rubyforge.org/projects/ruby-dbi).
>
> After unpacking ruby-dbi:
>
>    ruby setup.rb config --with=dbi,dbd_mysql
>    ruby setup.rb setup
>    ruby setup.rb install

This last step is a problem when you've installed Ruby using the one-click
installer because it tries to overwrite existing .rb files.  I had to delete
the existing ones to get this to work.

> You'll be good to go.

When I run my code that contains

  dbh = DBI.connect('dbi:Mysql:music:localhost', 'root', '')

I get

c:/Ruby/Ruby1.8.2-14/lib/ruby/site_ruby/1.8/dbi/dbi.rb:490:in `load_driver':  is
 not a class/module (TypeError)
        from c:/Ruby/Ruby1.8.2-14/lib/ruby/site_ruby/1.8/dbi/dbi.rb:392:in `_get
_full_driver'
        from c:/Ruby/Ruby1.8.2-14/lib/ruby/site_ruby/1.8/dbi/dbi.rb:372:in
`connect'

I looked at the code.  I think it's complaining about not being able to find a
class called DBI::DriverHandle.  That class is defined in dbi.rb.

Any idea what's going on here?

--
R. Mark Volkmann
Partner, Object Computing, Inc.