Take the 2-minute tour ×
WordPress Development Stack Exchange is a question and answer site for WordPress developers and administrators. It's 100% free, no registration required.
  1. Should I register both parent and child as 'hierarchical' => true, if there's no grandchild?

  2. If "Movie" is the top level taxonomy, when I register a child, is it as simply as: 'parent_item' => __( 'Parent Movie' )?

  3. How to automatically asign a child taxonomy to a post? So far, I figured out how to asign a taxonomy to a post, but, does this work fine with child taxonomy? wp_set_object_terms($post_ID, $cat, 'category');

  4. If I query a parent taxonomy, will the child be included in the results or not?

  5. If the taxonomies are not listed in the args of register_post_type, will they still work?

share|improve this question
add comment

2 Answers

up vote 1 down vote accepted

Too much for a comment, so I'll leave it for an answer:

  1. You're asking a lot of Qs that should actually be different Qs and not dumped into a single one.
  2. (Ad 1.) You don't register "child" or "parent" taxonomies. You add (child-)terms to a hierarchical taxonomy via the WP Back-End UI. You can do it programmatically with wp_set_post_terms();, wp_set_object_terms();, or other functions, but that's more internal stuff and tough to handle as you'd need to check on every request if it already exists or not (adds DB-queries), so it's not really recommended as you can't do it on theme activation as long as WP doesn't offer a hook there.
  3. (Ad 4.) You can query multiple taxonomies at one time as seen on the WP_Query article in Codex. This queries the taxonomy and all assigned posts. You can also query for terms that are inside a hierarchical taxonomy. But there are no "child" taxonomies. Only "child" terms. You can add those child terms to your tax_query arguments. Doing something like if is child of can be done with functions like get_term_children();. If you link to a term archive, you can modify the query (search WPSE) to include child terms as well.
  4. (Ad 3.) As stated in other answers & comments to some of your other Qs, you'll need to hook in stuff like save_post and similar. You'll find enough answers here on WPSE that show you how. You're close.
  5. (Ad 2.) You're mixing labels with actual arguments. The parent_item and parent_item_colon arguments are meant to set your custom text and can't register "child" taxonomies. They're only used to modify the default text you see in the admin UI.

Sidenotes:

  • Please care about your old Qs. We really got problems to lower the number of open & unanswered Qs. You should go back and try to work on your open Qs that have answers.
  • Proper formatting is highly appreciated. Answerers invest their time & advice for free to help you solve your problem. Please put an equal amount of effort into asking and formating a Q.
  • Be polite in your comments to an answer. This will a) motivate the answerer to offer further help and b) this is an open Q/A format and your Q is meant to help other users later to avoid asking the same Q again and instead just read your Q and the according answers. See your behavior when asking & commenting as something like your "buisness card".
share|improve this answer
    
Thanks for shading lights! Since WP codex says registering taxonomies for the child terms are required if a term is to be inserted, so I misunderstood that a term is also a taxonomy. –  Jenny Oct 19 '11 at 17:04
    
N/P. Also keep in mind that everything in wordpress is just a built-in/pre-configured taxonomy: categories, tags, etc. Could you also please provide a link to the codex article and tell me the exact position so I can clear things up? Thank you. –  kaiser Oct 19 '11 at 18:41
add comment

If you register a taxonomy as hierarchical=>true, it will become a category, and you can form parent - child relationships within that taxonomy. Whereas if you register a taxonomy as hierarchical=>false, it will become a tag, meaning, no parent - child relationships. You may need to get a term's id, use the function term_exists, then use wp_insert_term to insert a new term, with parent as the id you got using term_exists.

share|improve this answer
    
I guess you didn't really read my questions. –  Jenny Oct 19 '11 at 15:12
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.