Respond to taxonomy vocabulary deletion.
This hook is invoked after entity_bundle_delete() has been called and after the vocabulary has been removed.
Drupal\taxonomy\Plugin\Core\Entity\Vocabulary $vocabulary: The taxonomy vocabulary entity that has been deleted.
hook_taxonomy_vocabulary_predelete()
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_taxonomy_vocabulary_delete(Drupal\taxonomy\Plugin\Core\Entity\Vocabulary $vocabulary) {
db_delete('mytable')
->condition('vid', $vocabulary
->id())
->execute();
}