How can I get the machine name of a taxonomy term knowing its tid?

Question

Is there any table in the database that shows the relationship between vocabulary and taxonomy, or is there any way to find out the vocabulary name of a particular taxonomy from its tid?

Answer 1

The table taxonomy_term_data lists the terms, and taxonomy_vocabulary lists the vocabularies.

In the table taxonomy_term_data, the term string is found in the name field. The field vid identifies the vocabulary assocaiated with the term. And the field tid is the numeric taxonomy id.

So you can look up the relationship between the term name, tid and vid directly from the this table.

Then, to determine the vocabulary name string associated with the term, you need to left join the taxonomy_vocabulary.name field, where taxonomy_vocabulary.vid = taxonomy_term_data.vid.

Answer 2

Using the API would be preferable to going into the database directly as you can take advantage of caching properly, and keep a more structured code base at the same time:

$term = taxonomy_term_load($tid);
$vocab = taxonomy_vocabulary_load($term->vid);
$machine_name = $vocab->machine_name;

Answer 3

If you have the taxonomy term ID, it is enough you call taxonomy_term_load().

$term = taxonomy_term_load($tid);
$vocabulary_name = $term->vocabulary_machine_name;

Using the Devel module, you can notice the object returned from taxonomy_term_load() contains the following fields.

With Drupal 8, each entity has its own PHP class, contrary to previous Drupal versions where each entity instance is a stdClass object.

In Drupal 7, if you don't have a taxonomy term ID, and you want to load all the taxonomy terms, you should use the EntityFieldQuery class; see How to use EntityFieldQuery. In Drupal 8, entity_load_multiple_by_properties() is the function you should use.

Answer 4

With D8 something like this.

$parameters = \Drupal::routeMatch()->getParameters()->all();
if (isset($parameters['taxonomy_term'])) {
  $term = $parameters['taxonomy_term'];  
  $vid = $term->bundle();
  $vocabulary = \Drupal::entityTypeManager()->getStorage('taxonomy_vocabulary')->load($vid);
  $vocabulary_label = $vocabulary->label();
}