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.

196 open tickets in the Taxonomy component

196 open tickets defect (bug) enhancement feature request task (blessed)
26 28 1 0
5.4 2 1 0 0
Awaiting Review 52 30 10 0
Future Release 20 20 5 1

196 open tickets. Last 7 days: +1 ticket

50 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
  • #38265  Add term_relationship_id column to wp_term_relationships
  • #38278  Only query taxonomies assigned to the post types being queried
  • #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
  • #44088  Merged two if into single template
  • #44630  WP_Term_Query does not return all terms when 'number' and 'object_ids' are specified
  • #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
  • #45393  categories don't work in brand-new wordpress instance (return 404)
  • #45722  add markup to highlight the active tag
  • #45938  Adding new term meta fails if column is wrapped in a conditional
  • #46166  wp_update_term sanitizes the description, removing all html
  • #46338  taxonomy_meta_box_sanitize_cb_checkboxes: Warning: array_map(): Expected parameter 2 to be an array, string given
  • #46482  Non-hierarchical taxonomies using checkbox display are not saving in quick edit
  • #47029  Custom Taxonomies, with no post_type association and custom submenu location, UX experience is broken when on Taxonomy management page
  • #47314  Add "parent" parameter to get_term_by
  • #47351  term_exists() needs to apply_filters('pre_term_name') to match wp_insert/update_term()
  • #48000  Administration – Edit Page for Meta Data on Taxonomies ui administration
  • #48176  Deprecated get_all_category_ids() call can return incorrect results
  • #48220  Category Dropdown Layout Issue
  • #48284  MIsleading behavior and documentation in include argument of WP_Term_Query docs
  • #48394  PHPDoc correction for functions in wp-includes/category-template.php docs
  • #48416  Add `saved_term` actions that fire on create and update
  • #48498  Walker_Category should also accept the `item_spacing` parameter.
  • #48558  Return the taxonomy object in register_taxonomy()

3 tickets slated for 5.4

View list in Trac

  • #38545  Add span element to get_the_archive_title()
  • #43345  term_exists() may return 0 which is not a text-documented return type docs
  • #48394  PHPDoc correction for functions in wp-includes/category-template.php docs

196 open tickets

Open bugs: 100. View list on Trac

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