Lester Caine wrote:

> Of cause in that situation you need to block activity on the database
> until you have finished. My usual approach is just to 'close' the site
> (switch to maintenance message) and restart Apache.

I have many applications running and using different databases. While
one db is updated, others should be able to keep running. I solved it
by creating a dummy lock file. Each page in my web apps has a line:

require_once('login.php');

Which in turn uses file_exists() to check if lock file is there. If it
is, it locks the users out until database is updated.

> I would still maintain that structural changes should be made on a copy
> of the data and that live data would be pumped in when you are happy,
> but I'm not enforcing that rule as strongly as I used to :)

And it's error prone with generators and all that stuff ;)

--
Milan Babuskov
http://njam.sourceforge.net
http://swoes.blogspot.com