Best place to put AKA reading database from the config file..

[eluser]Narkboy[/eluser]
I'm building a series of apps that work together to produce a series of e-commerce sites all drawing data from a common source.

Effectively we have:

EPOS Data Source <-----&gt; Config Site <------&gt; Public Sites (3 planned, more to come)

The Config Site is the only place that the web manager will be able to make changes, and these changes can be site-specific or cover all end sites.

The data in the cofig site must be manually updated from the EPOS data source - and this can take quite a lot of time (500k+ records checked and ammended or created as required). PITA, but unaviodable.

Amongst other things, the config site will have a master 'active' switch for each end site that will enable fast transition between the site being operational and displaying a maintenance page to permit updates.

The question is - how far up the CI process can I place this switch? I'd love to put it in the config file, so it's checked early, but I'm wary of putting a database call 1) inside the config file and 2) outside the standard method of accessing the db (using active record).

Suggestions / ideas / 'heres what I did's please!

Thanks!!