Taxonomy component

What is Taxonomy?

WordPress data objects, such as posts and users, can be grouped using taxonomy terms. A term is a grouping entity that exists in many-to-many relationships with other entities. A taxonomy is a grouping of terms, within which terms must be unique. WordPress ships with a number of built-in taxonomies, such as the hierarchical categories and the non-hierarchical tags. Since version 2.3, WordPress has also allowed plugins and themes to register custom taxonomies. A number of auxiliary WP features, like post formats and nav menus, are powered in part by taxonomy terms.

What does the Taxonomy component include?

The Taxonomy component covers:

  • The custom taxonomy API: register_taxonomy(), etc
  • Business functions for the creation, retrieval, updating, and deletion of taxonomy terms: wp_insert_term(), get_terms(), etc
  • Dashboard panels for managing taxonomy terms, such as edit-tags.php, and the parts of the Posts interface that are used to manage taxonomy term relationships, such as the Categories and Tags metaboxes

Ongoing projects

We have an ambitious taxonomy roadmap, and have been making incremental progress on a few large projects during the last few major WordPress releases. See ‘taxonomy’ posts on make/core for some background.

In WordPress 4.4, we’re beginning work on a few new projects:

  • Better data modeling and WP_Term #14162
  • Combining the wp_terms and wp_term_taxonomy tables #30262
  • Term meta #10142

Recent posts on the make/core blog

View all posts tagged taxonomy.

Recent posts on the make/test blog

View all posts tagged taxonomy.

206 open tickets in the Taxonomy component

206 open tickets defect (bug) enhancement feature request task (blessed)
5.1 6 3 0 0
Awaiting Review 68 41 9 0
Future Release 30 36 5 1
5.0.1 0 7 0 0

206 open tickets. Last 7 days: +1 ticket

45 tickets that have no replies

View list on Trac

  • #32788  Moving sublevel menu item still opens the dropdown menu in the original location. administration
  • #33585  Improve wp_list_categories to support multiple taxonomies
  • #34752  Confirmation for bulk delete on tax terms administration
  • #35385  Able to get raw content by calling get_the_archive_description template
  • #35504  response to adding data to taxonomy shows in a wrong place ui javascript
  • #36399  Change function signature of `wp_count_terms()` to be compliant with recent `get_terms()` changes
  • #36428  Weird default value of option 'default_link_category'
  • #36610  Loss of multibyte category and tag names
  • #36956  Trigger event when taxonomy term is added with ajax administration
  • #36978  Add pre filter to get_term_by
  • #37662  Category sub-category problem
  • #37728  hide_empty doesn't work correctly in get_terms when no taxonomy specified
  • #38243  Attempting to create a term with invalid UTF8 characters creates a blank term
  • #38265  Add term_relationship_id column to wp_term_relationships
  • #38278  Only query taxonomies assigned to the post types being queried
  • #38810  Add level class to terms list-table rows administration
  • #39406  Make callback_args filterable in WP_Terms_List_Table
  • #39678  get_term_by slug with "0" as value
  • #39754  `_post_format_get_terms()` can overwrite names of terms in other taxonomies
  • #39969  add filter to end of post_categories_meta_box()
  • #40232  Could is_tax check through queried_terms instead of queried_object?
  • #40291  subcategory pagination no run
  • #40696  no chance to control wp_count_terms ()
  • #40757  Standardize Application of 'the_category' Filter
  • #41631  Same Term Not Added
  • #41702  Slug for Category or Tag should be generated automatically ui administration
  • #41776  wp_list_category array element 'exclude' better be called 'exclude_id'
  • #41878  No way to change the order of fields for taxonomy meta
  • #41882  Walker_CategoryDropdown does not wrap options inside HTML select element with wp_list_categories
  • #42005  filter get_terms_args and orderby meta_value_num not working as expected ui administration
  • #42104  Tax query transformations unintentionally filtered by 'terms_clauses'
  • #42572  Can't delete custom taxonomy tags from a post
  • #43345  term_exists() may return 0 which is not a text-documented return type
  • #43703  Edit Category screen – Error shown in green and admin notice not dismissible. administration
  • #44088  Merged two if into single template
  • #44630  WP_Term_Query does not return all terms when 'number' and 'object_ids' are specified
  • #44854  Bulk action missing/hidden on taxonomies ui administration
  • #44880  Missing sanitization coding-standards
  • #44969  Add support to limit results in get_objects_in_term()
  • #45085  different args passed to "term_name" and "term_{$field}" filters docs administration
  • #45092  WP_Query->is_category wrongly calculate current category when WP_Term is passed
  • #45163  get_term_by() should accept ID as a field
  • #45251  Taxonomy `lang` not working in custom post with WP version 5.0 beta 2 javascript administration
  • #45297  _wp_ajax_menu_quick_search: Deprecated taxonomy input for get_terms administration
  • #45333  term_exists might fail if slugs are changed

9 tickets slated for 5.1

View list in Trac

  • #36514  posting with custom taxes administration
  • #38922  Use REST API for ajax tag search rest-api
  • #43345  term_exists() may return 0 which is not a text-documented return type
  • #43516  Allowing default category to be applied to all CPT associated to 'category' taxonomy
  • #43517  Adding support of default category term for custom taxonomies
  • #43703  Edit Category screen – Error shown in green and admin notice not dismissible. administration
  • #43743  Terms list table should be full width when user cannot edit terms administration
  • #44466  Have a method to check if a taxonomy is viewable
  • #45297  _wp_ajax_menu_quick_search: Deprecated taxonomy input for get_terms administration

206 open tickets

Open bugs: 104. View list on Trac

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