Open Query Builder

I am trying to edit a table to include one additional column but I cannot open the table to edit it. The Open Query Builder does not do anything. How can I edit a table that is in the table browser?

The Table browser is only used to view your DB structure and to quickly create SELECT statements. You can manage your DB tables in the GUI you used to create these tables (PHPMyAdmin, MSSM studio, MySql workbench, etc…) or via the terminal of the server running the SQL/MySQL instance.