Chris@0: /**
Chris@0:  * Implements hook_entity_predelete().
Chris@0:  */
Chris@0: function {{ machine_name }}_entity_predelete(Drupal\Core\Entity\EntityInterface $entity) {
Chris@4:   $connection = \Drupal::database();
Chris@0:   // Count references to this entity in a custom table before they are removed
Chris@0:   // upon entity deletion.
Chris@0:   $id = $entity->id();
Chris@0:   $type = $entity->getEntityTypeId();
Chris@4:   $count = \Drupal::database()->select('example_entity_data')
Chris@0:     ->condition('type', $type)
Chris@0:     ->condition('id', $id)
Chris@0:     ->countQuery()
Chris@0:     ->execute()
Chris@0:     ->fetchField();
Chris@0: 
Chris@0:   // Log the count in a table that records this statistic for deleted entities.
Chris@4:   $connection->merge('example_deleted_entity_statistics')
Chris@0:     ->key(['type' => $type, 'id' => $id])
Chris@0:     ->fields(['count' => $count])
Chris@0:     ->execute();
Chris@0: }