Bits of .NET

Even with page caching (like WP Rocket), your database can still crawl. Persistent Object Caching stores the results of complex SQL queries in RAM using Redis.

// Verify if Object Cache is active
$cache_info = wp_cache_get('my_complex_query_result');
if ( false === $cache_info ) {
    $cache_info = $wpdb->get_results("SELECT... LARGE QUERY");
    wp_cache_set('my_complex_query_result', $cache_info, '', 3600);
}

This reduces Time to First Byte (TTFB) by bypassing the disk-bound database for repeat data requests.