I've been wanting to upgrade to MySQL 5 for a while now, and after hearing that MySQL 5 is required for Drupal 7 I decided to bump up my upgrade schedule, pronto. If all one wants is MySQL 5 then that is easy enough -- go download MAMP and you're done. But what if you want to be able to dev on MySQL 4 for projects that require it for whatever reason (e.g., clients who are run it and are not willing/able to upgrade MySQL at the moment)?
Well, with not a lot of effort - it very easy to have a PHP 5, PHP 4, MySQL 5, and MySQL 4.1 environment - all sharing the same doc root and servernames (e.g., urls):
Configure Apple's native Apache, PHP, and add a free-standing MySQL 4.1 install (since MAMP comes with MySQL 5, right). Here are two good links to get you on your way to doing this:
Install Drupal on Mac OS X 10.5 Leopard
Working with PHP 5 in Mac OS X 10.5 (Leopard)
...if you are migrating a free-standing MySQL install from a previous install you may want to check these articles out (1, 2) as well.
Note: Getting all of this totally set up and working right, including setting up your virtualhosts and /etc/hosts file, before installing MAMP will pay off.
Download MAMP and follow the readme.txt instructions and/or use these links to setup the basics:
HowTo: Create a local environment using MAMP
Install a Local Web Server on Mac OSX
Now it's time to integrated these two completely separate environments so that you can keep a common doc root, virtualhosts, and urls, and systems tools (we'll get terminal access going for MAMP's MySQL):
We'll make it so that we can keep all of our sites, no matter which enviroment they require, in a common place -- and so that no matter what we're running we will always be able type in "localhost", or and know that it will take us to our doc root (instead of having to remember to type "localhost:8888/" for MAMP:). Relatedly, doing the steps below lets us keep common server names (e.g., 'mysite.local') across environments.
* Change the docroot in MAMP's httpd.conf (line 368) to: