Upgrading PHP to version 5.4 on Ubuntu

[UPDATE]: I've recently used this approach on a 64-bit Ubuntu Server ( clean install) and it seems to have worked so that's good news for me and praise to Ondřej Surý who maintains that ppa!

If you're using a version of Ubuntu which has still got PHP 5.3++ in its repositories, this is what you need to do do upgrade PHP to version 5.4 and start using its new features:

• add this PPA to your ubuntu sources:

  sudo add-apt-repository ppa:ondrej/php5
  

• now update the files per se:

  sudo apt-get update
  sudo apt-get upgrade
  sudo apt-get dist-upgrade
  

• References:

  • stack overflow question on upgrading php to 5.4
  • barry o'donovan post on upgrading php to 5.4 on precise pangolin

Troubleshooting

• sudo: add-apt-repository: command not found

  You need to install python-software-properties first:

  sudo apt-get install python-software-properties
  

• re-installing APC

  I used this to upgrade my PHP version at home. I was asked whether I wanted to replace my php.ini version with the one that came with the new upgrade. I said no.

  Maybe because of that, some of the extensions I use (like apc and some pdo drivers) couldn't be found when I tried to run my apps after upgrading PHP like this.

  I ended up needing to re-install apc, which is easy enough:

  sudo pecl uninstall apc
  sudo pecl uninstall apc-beta
  sudo pecl install apc-beta
  

  Restart Apache