Hello, My server is running php and mysql 4. Should I upgrade to 5? Is there any incompatible issue? Thanks.
i would recommend it. as for compatability issues, i had no problems during my upgrade but of course that all depends on how you code. i wish hostgator would run mysql5 stored procedures rock my socks..
It's a good idea to upgrade, but you should do so only after testing your application for any errors that may pop up. A good developer has a production server and a test server where thats identical. This way they can develop on the test server and know that everything will be fine when its uploaded to the production one. So ya, get yourself a development environment, like Linux in VMWare if you run Windows, where you can test things out.
I would switch to PHP 5 (not sure about MySQL 5) just out of development considerations. PHP 5 is faster, it's OOP implementation is much better, and the DOM model works better than in PHP 4.
From my experience it's a good idea to move to php5 from php4. If you want to upgrade your mySQL then you may have to do much more testing than for the php upgrade.
As every else has stated test your application first! Time and time again people upgrade to newer versions in the production environment without ever testing things in a test environment. So I'd put up a php5 + mysql 5 configuration on your computer if you can to make sure there are no errors. There are several changes that could break your scripts in php5 anyways so I'd check out php.net/manual/en/migration5.php . Now for MySQL5 there are some queries that may break depending on the way you did joins so I'd check that out as well. If you do manage you migrate you'll find things faster if you made use of OO on the php side originally. MySQL I'm sure there are some speed improvements maybe but it's mostly added features.