Steps to upgrade MySQL from version 5.0 to version 5.5

The following steps require the EPEL (Extra Packages for Enterprise Linux) so you’ll have to install epel first before proceeding. Here’s the command:

#rpm -Uvh http://dl.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm

Step 1: login as root to your vps 

Step 2: Install Remi repository

 #rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-5.rpm

The result will something like..

Retrieving http://rpms.famillecollet.com/enterprise/remi-release-5.rpm
warning: /var/tmp/rpm-xfer.cVJJxn: Header V3 DSA signature: NOKEY, key ID 00f97f56
Preparing... ########################################### [100%]
1:remi-release ########################################### [100%]

Step 3: Check availability of MySQL versions

#yum --enablerepo=remi,remi-test list mysql mysql-server

The last lines of the output should be something like this:- Available Packages

mysql.i386 5.5.14-1.el5.remi remi
mysql-server.i386 5.5.14-1.el5.remi remi
[root@one ~]#

Step 4: Update or Install MySQL

#yum --enablerepo=remi,remi-test install mysql mysql-server

Step 5: Restart MySQL

#service mysqld start

Step 6: Upgrade MySQL Databases

#mysql_upgrade -u root -p

NOTE : THE LAST STEP IS VERY IMPORTANT BECAUSE IT WILL CREATE PRIVILEGE TABLES