A very nice alternative to phpmyadmin is a free script called Eskuel. It is very easy to use, clean and simple layout and very quick navigation.
A great feature is the ability to easily add multiple databases and manage them on a single interface. So far Eskuel has been able to accomplish anything I’ve needed to do with a MySQL database.
You may also try AeroSQL: http://www.burlaca.com/aerosql/
AeroSQL is a free web based tool for managing MySql servers written in PHP. The key feature of the product is an intuitive management of the database content. The result of SELECTs is displayed in a grid as in traditional desktop applications. The grid is editable: you can update cells and save the changes to the backend database server. For now, the query browser represents the main functionality. Additional features will be added in the next versions: administration tools (backup, restore), database object management (create tables).