How do I clear the cache for a single node? In my module, I can call cache_clear_all() (D7) or drupal_flush_all_caches() (D8), and this would clear the cache for all the nodes. 

Is there a way to clear the cache for a single node?

What I need to do is setting up a module that, when it selects a story on a list, it changes the value of a node field. Right now, I change the field value by updating the database table containing that value, but I need to clear the cache for the value to be updated across the site. 

Is there's a better way to update a node than directly changing the database table?
If you have the node object, use

use Drupal\Core\Cache\Cache;
...
Cache::invalidateTags($node-&gt;getCacheTags());


That's better than to assume the cache tag identifier will be 'node:' . $node-&gt;id() forever.