An example wp-config.php

edited-wp-config.php

// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define( 'DB_NAME', 'new_db_name' ); # CHANGE THIS!

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

/** MySQL database password */
define( 'DB_PASSWORD', 'existing_db_password' );

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

wp-config.php

// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define( 'DB_NAME', 'existing_db_name' );

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

/** MySQL database password */
define( 'DB_PASSWORD', 'existing_db_password' );

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