How to send queries to a database periodically

[Peter PeterDresden]

Hi,

is there a possibillity in mysql to send periodically queries to a database, 
for example all 5 minutes? Or, a liitle bit off topic, is there a 
possibility to this via php? Or, is it normally possible to set up such a 
query via  cron tab (unix based web servers only)? Thanx.