$php_compat = version_compare( $php_version, $required_php_version, '>=' );
if ( file_exists( WP_CONTENT_DIR . '/db.php' ) && empty( $wpdb->is_mysql ) )
$mysql_compat = true;
$php_compat = version_compare( $php_version, $required_php_version, '>=' );
if ( file_exists( WP_CONTENT_DIR . '/db.php' ) && empty( $wpdb->is_mysql ) )
$mysql_compat = true;