Rails - May 2005 - Database Connection Issues

Rails community -

1. Does Rails make a new connection to the Database for each request?

2. I am trying to specify which database to connect to for each model.  
I have added these lines of code into my config/environment.db file:

Recipe.establish_connection(
    :adapter => "mysql",
    :host => "localhost",
    :username => "dderaps",
    :password => "buzz05",
    :database => "derek"
)

Category.establish_connection(
    :adapter => "mysql",
    :host => "localhost",
    :username => "dderaps",
    :password => "buzz05",
    :database => "derek2"
)

The following happens: when I go to
    http://localhost/recipe/list
      or
    http://localhost/category/list
the first time, everything works works fine, but, for each subsequent 
request, it defaults to using the database defined in config/database.yml.

According to MySQL administrator, those initial two connections to 
databases "derek" (for Recipe) and "derek2" (for Category)
remain
connected to the database server.

I have also tried putting the above code in the controller and/or model, 
and that works, but that creates a new connection every time and does 
not close it, which is a problem because after 25 requests I have 50 
connections to the database server.

Any hints, tips, comments, or suggestions on setting up models to use 
different databases?
Also any advice on optimizing Rails database access for taking huge 
amounts of hits? (such as not making a new connection to the database 
server every time, just using a pre-existing connection from the pool)

Thanks guys and gals,
Derek DeRaps

On May 27, 2005, at 8:16 AM, Derek DeRaps wrote:
> Rails community -
> 1. Does Rails make a new connection to the Database for each request?
By default, your app makes a single connection for the lifetime of  
your dispatcher: for webrick, until you stop the server; for  
mod_ruby, until the Apache worker dies; for FastCGI, until the  
FastCGI instance is reaped; and per-request for CGI.

> 2. I am trying to specify which database to connect to for each  
> model.  I have added these lines of code into my config/ 
> environment.db file:
You may prefer to put the recipe and category config in your  
database.yml as, say, recipe-dev, recipe-test, recipe-production,  
etc.  Then make your custom connections in environment.rb as  
Recipe.establish_connection "recipe-#{RAILS_ENV}".

> The following happens: when I go to http://localhost/recipe/list
> the first time, everything works works fine, but, for each  
> subsequent request, it defaults to using the database defined in  
> config/database.yml.
Hmm.  I suspect that the auto-reloading in the development  
environment is wiping your database connection.  Could you try in the  
production environment?  This is a bug (over-eager reloading) if it  
works in production but not development.

Best,
jeremy