Say Goodbye to ‘get_terms’, Use ‘WP_Term_Query’

WordPress 4.6 introduces a new class for querying taxonomies. Like WP_Query,WP_User_Query,and WP_Comment_Query.

When using WordPress own query classes, you can be at ease – all caching and security measures are done by

WordPress core. So you don’t need to write your complex, insecure SQL queries to your WordPress DB.

Example

Here $args holds various parameters to query taxonomies.

Parameters

  • ‘taxonomy’
    (string|array) Taxonomy name, or array of taxonomies, to which results should be limited.
  • ‘orderby’
    (string) Field(s) to order terms by. Accepts term fields (‘name’, ‘slug’, ‘term_group’, ‘term_id’, ‘id’, ‘description’), ‘count’ for term taxonomy count, ‘include’ to match the ‘order’ of the $include param, ‘meta_value’, ‘meta_value_num’, the value of$meta_key, the array keys of $meta_query, or ‘none’ to omit the ORDER BY clause. Defaults to ‘name’.
  • ‘order’
    (string) Whether to order terms in ascending or descending order. Accepts ‘ASC’ (ascending) or ‘DESC’ (descending). Default ‘ASC’.
  • ‘hide_empty’
    (bool|int) Whether to hide terms not assigned to any posts. Accepts 1|true or 0|false. Default 1|true.
  • ‘include’
    (array|string) Array or comma/space-separated string of term ids to include.
  • ‘exclude’
    (array|string) Array or comma/space-separated string of term ids to exclude. If $include is non-empty, $exclude is ignored.
  • ‘exclude_tree’
    (array|string) Array or comma/space-separated string of term ids to exclude along with all of their descendant terms. If $include is non-empty, $exclude_tree is ignored.
  • ‘number’
    (int|string) Maximum number of terms to return. Accepts ”|0 (all) or any positive number. Default ”|0 (all).
  • ‘offset’
    (int) The number by which to offset the terms query.
  • ‘fields’
    (string) Term fields to query for. Accepts ‘all’ (returns an array of complete term objects), ‘ids’ (returns an array of ids), ‘id=>parent’ (returns an associative array with ids as keys, parent term IDs as values), ‘names’ (returns an array of term names), ‘count’ (returns the number of matching terms), ‘id=>name’ (returns an associative array with ids as keys, term names as values), or ‘id=>slug’ (returns an associative array with ids as keys, term slugs as values). Default ‘all’.
  • ‘name’
    (string|array) Optional. Name or array of names to return term(s) for.
  • ‘slug’
    (string|array) Optional. Slug or array of slugs to return term(s) for.
  • ‘hierarchical’
    (bool) Whether to include terms that have non-empty descendants (even if $hide_empty is set to true). Default true.
  • ‘search’
    (string) Search criteria to match terms. Will be SQL-formatted with wildcards before and after.
  • ‘name__like’
    (string) Retrieve terms with criteria by which a term is LIKE $name__like.
  • ‘description__like’
    (string) Retrieve terms where the description is LIKE $description__like.
  • ‘pad_counts’
    (bool) Whether to pad the quantity of a term’s children in the quantity of each term’s “count” object variable. Default false.
  • ‘get’
    (string) Whether to return terms regardless of ancestry or whether the terms are empty. Accepts ‘all’ or empty (disabled).
  • ‘child_of’
    (int) Term ID to retrieve child terms of. If multiple taxonomies are passed, $child_of is ignored. Default 0.
  • ‘parent’
    (int|string) Parent term ID to retrieve direct-child terms of.
  • ‘childless’
    (bool) True to limit results to terms that have no children. This parameter has no effect on non-hierarchical taxonomies. Default false.
  • ‘cache_domain’
    (string) Unique cache key to be produced when this query is stored in an object cache. Default is ‘core’.
  • ‘update_term_meta_cache’
    (bool) Whether to prime meta caches for matched terms. Default true.
  • ‘meta_query’
    (array) Meta query clauses to limit retrieved terms by. See WP_Meta_Query.
  • ‘meta_key’
    (string) Limit terms to those matching a specific metadata key. Can be used in conjunction with $meta_value.
  • ‘meta_value’
    (string) Limit terms to those matching a specific metadata value. Usually used in conjunction with $meta_key.

Retrieve terms in category

 

Leave a Reply

4 Comments

  1. Can I use this to query custom taxonomies that are registered to other objects like User?

  2. dzeriho

    This is the second line of the get_terms() function:

    $term_query = new WP_Term_Query();

    So, I really have no idea what’s your trick is about. You should remove that. Thanks.

    • Dhinju Divakaran

      After WP 4.6 get_terms() function is a wrapper for WP_Term_Query. Like get_posts and WP_Query. Using WP_Term_Query avoids an additional function call. Thanks for your valuable comment.

  3. Hi Dhinju

    this is great, thanks for sharing.

    is there any way I can get the last term of the current taxonomy post?

    so far I’ve tried this but it shows all parent terms , where as i just want to show the last ancestor of the current post i’m on.

    hoping you can help

    $term_query = new WP_Term_Query(

    array (
    ‘taxonomy’ => ‘region’,
    ‘parent’ => 0,
    ‘orderby’ => ‘id’
    )
    );

    if ( ! empty( $term_query->terms ) ) {
    foreach ( $term_query ->terms as $term ) {

    echo ‘‘ . $term->name . ‘‘;
    }

    }

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