WordPress Database
Interfacing With the Database
WordPress provides a class of functions for all database manipulations. The class is called wpdb .
WordPress provides a global variable, $wpdb, which is an instantiation of the class already set up to talk to the WordPress database. Always use the global $wpdb variable. (Remember to globalize $wpdb before using it in any custom functions.
The $wpdb object can be used to read data from any table in the WordPress database (such as custom plugin tables), not just the standard tables that WordPress creates.
