Querying the database

As with most frameworks, WordPress provides a built-in interface for interacting with the database. Most of the database operations will be handled by the wpdb class located inside the wp-includes directory. The wpdb class will be available inside your plugins and themes as a global variable and provides access to all the tables inside the WordPress database, including custom tables.

Note

Using the wpdb class for CRUD operations is straightforward with its built-in methods. A complete guide for using the wpdb class can be found at http://codex.wordpress.org/Class_Reference/wpdb.

Querying the existing tables

WordPress provides well-optimized built-in methods for accessing the existing database tables. Therefore, accessing these tables becomes straightforward. Let's see how basic Create, Read, Update, Delete (CRUD) operations are executed on existing tables.

Inserting records

All the existing tables contain a prebuilt insert method for creating new records. The following list...