Check out example codes for "how to use mysql databast hostgator with a wordpress install". It will help you in understanding the concepts better.

Code Example 1

// ** MySQL Settings ** //
/** The name of the database for WordPress */
define('DB_NAME', 'joe1337_wrdp1');

/** MySQL database username */
define('DB_USER', 'joe1337_wp1');

/** MySQL database password */
define('DB_PASSWORD', 'eHTb7%Pxa9');

/** MySQL hostname */
define('DB_HOST', 'localhost');

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