What is wp-config.php in WordPress?
The wp-config.php file is one of the essential WordPress files required for the content management system to work properly. This configuration file specifies key information WordPress needs to connect to the database and store site data.
When you download WordPress, wp-config.php is not included by default. Instead, there is a sample file called wp-config-sample.php that serves as a template. By renaming this file to wp-config.php and customizing it with your database details, you enable WordPress to communicate with the database.
Database Connection Details
The main purpose of wp-config.php is to provide the database information for your WordPress site. This allows WordPress to access the database via PHP and perform CRUD operations on-site data.
The config file contains variables like DB_NAME, DB_USER, DB_PASSWORD, and DB_HOST that must be configured with your database credentials. For example, DB_NAME would contain your actual database name.
Here is an example of the database configuration section:
// ** MySQL settings - Get this from your web host ** //
/** The name of the database for WordPress */
define('DB_NAME', 'database_name_here');
/** MySQL database username */
define('DB_USER', 'username_here');
/** MySQL database password */
define('DB_PASSWORD', 'password_here');
/** MySQL hostname */
define('DB_HOST', 'localhost');Without this correct database information, WordPress will be unable to connect to the database and key site functionality will break.
Advanced Configuration Settings
In addition to the database details, wp-config.php contains other advanced configuration settings for WordPress.
For example, security keys and salts are specified to improve security and generate hashes. The table prefix for the WordPress database tables can also be customized.
Developers can toggle debugging settings and constants for performance tuning. Localization and language settings are defined in wp-config.php as well.
Here is an example of some additional settings found in the file:
/**#@+
* Authentication Unique Keys and Salts.
*/
define('AUTH_KEY', 'put your unique phrase here');
define('SECURE_AUTH_KEY', 'put your unique phrase here');
/**
* WordPress Database Table prefix.
*/
$table_prefix = 'wp_';
/**
* WordPress Localized Language.
*/
define('WPLANG', 'en_US');While the database settings are necessary, these extra configurations help optimize and secure the WordPress installation.
Generated for Each Site
Because the wp-config.php file contains sensitive information specific to that database, a separate config file is needed for each WordPress site.
The details in wp-config.php like database name and password uniquely apply to that particular site and its hosting environment. This is why the file must be configured individually when setting up a new WordPress site.
The same wp-config.php file cannot be reused across different WordPress sites since the database details will differ. Consider it a required per-site configuration file.
Storing Outside Web Root
For security reasons, the wp-config.php file should be stored one level above the WordPress web root folder. This prevents the file from being accessed directly via a web browser.
As an example, if WordPress core files are stored in /var/www/html/wp-folder, wp-config.php should be saved in /var/www/html. This adds protection since the config file contains sensitive credentials.
Proper placement of wp-config.php prevents the information within from being exposed publicly.
Changes Require Manual Updates
Because wp-config.php contains hardcoded configurations, changes to settings like the database password must be manually updated in the file itself.
The settings do not dynamically pull from anywhere else. So, if you change your database credentials, you would need to open the file and modify the values stored there.
This is in contrast to other WordPress settings that are saved in the database itself. Those can be updated via the admin dashboard without editing PHP files.