My::DB->register_db(
  domain   => 'development',
  type     => 'main',
  driver   => 'Pg',
  database => 'dev_db',
  host     => 'localhost',
  username => 'devuser',
  password => 'mysecret',
  server_time_zone => 'UTC',
);
 
My::DB->register_db(
  domain   => 'production',
  type     => 'main',
  driver   => 'Pg',
  database => 'big_db',
  host     => 'dbserver.acme.com',
  username => 'dbadmin',
  password => 'prodsecret',
  server_time_zone => 'UTC',
);


##</code><code>##

# File: startup.pl
use My::DB;
 
if($ENV{'MYCORP_PRODUCTION_SERVER'})
{
  My::DB->default_domain('production');
}
else
{
  My::DB->default_domain('development');
}