Expanded class hierarchy of Update

class \Drupal\Core\Database\Query\Query implements PlaceholderInterface
- class \Drupal\Core\Database\Query\Delete implements ConditionInterface
- class \Drupal\Core\Database\Query\Insert
- class \Drupal\Core\Database\Query\Merge implements ConditionInterface
- class \Drupal\Core\Database\Query\Select implements SelectInterface
- class \Drupal\Core\Database\Query\Truncate
- class \Drupal\Core\Database\Query\Update implements ConditionInterface
  - class \Drupal\Core\Database\Driver\mysql\Update
  - class \Drupal\Core\Database\Driver\pgsql\Update
  - class \Drupal\Core\Database\Driver\sqlite\Update