if ( ! function_exists( 'wpb_copyright' ) ) { function wpb_copyright() { // Cache the output so we don't have to run the query on every page load. $output = get_transient( 'wpb_copyright_text' ); if ( false !== $output ) { // Return the cached output. return $output; } global $wpdb; $copyright_dates = $wpdb->get_results( "SELECT YEAR(min(post_date_gmt)) AS firstdate, YEAR(max(post_date_gmt)) AS lastdate FROM $wpdb->posts WHERE post_status = 'publish'" ); $output = ''; if ( $copyright_dates ) { $output = '© ' . $copyright_dates[0]->firstdate; if ( $copyright_dates[0]->firstdate !== $copyright_dates[0]->lastdate ) { $output .= '-' . $copyright_dates[0]->lastdate; } // Set the value as a transient so we only run the query 1x per day. set_transient( 'wpb_copyright_text', $output, DAY_IN_SECONDS ); } return $output; } } echo wpb_copyright();