I recently add an new server for mysql, and moved magento database to new server.
I Restore database to new mysql and alter the configuration (in Web server) in app/etc/local.xml file
Removed cache, Magento admin panel > System > Cache management And deleting the contents of the var/cache and var/session folders inside Magento installation directory.
Now, Problem is, all of magento connect to new database connection Except product pages. Because than i stop old mysql service only product page show connection lost.
I think, there is an other cached configuration file, maybe!