A typical configuration file for MySQL 5.1 would be something like this (link downloads the my.cnf from our FogBugz instance). These numbers are geared toward a server only running FogBugz and MySQL using 2GB of RAM. I would scale the numbers linearly if you have more RAM than that UNLESS you have an large amount (more than 32GB of RAM). If you have that much RAM, consult your DBA about correct values.
This file is made for use with 5.1. Bear in mind that this will also work for MySQL 5.5, but NOT for MySQL 5.0 due to variable renaming. Most of the variables have similar options in MySQL 5.0. You can find the list of them for MySQL 5.1 here and the MySQL 5.0 options here.
Finally, there are several path-related variables in the file. They were originally written for Linux, which obviously has a fair amount of variety in where you might store your sockets and PIDs… And Windows is a completely different beast. Make sure you go through and change those variables to be relevant to your installation before using this. You can always compare those paths to the paths in the default my.cnf/my.ini file to know what they should be.
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