Caching is built-in function in Drupal.
After enabling caching, Drupal will begin storing database in a special tables that allows for faster respone times. So, this caching table can be out of sync with the underlying data.
You can also set 'Minimum cache lifetime' or 'Expiration of cached pages'. And of course, the 'Clear all caches' will force Drupal to retrieve the latest data as it rebuils the cache.
Caching is built-in function in Drupal. After enabling caching, Drupal will begin storing database in a special tables that allows for faster respone times. So, this caching table can be out of sync with the underlying data. You can also set 'Minimum cache lifetime' or 'Expiration of cached pages'. And of course, the 'Clear all caches' will force Drupal to retrieve the latest data as it rebuils the cache.