remove a single post_meta

Question

I created a plugin that has multiple meta boxes. One meta box saves a single record by using update_post_meta(). Another meta box saves multiple record by using add_post_meta().

I do not have revisions turned on in the post_type.

How would you delete_post_meta() a single specific record in the meta box that uses add_post_meta()? Best practice advise is needed.

If you're going to send the whole $post->ID and it will get the array of records, how can I detect the specific meta_key set to be deleted?

Here is the code on github: https://github.com/fritzdenim/stec-events/blob/62d5c641622f75a610da09462260f09713f0abab/index.php

Answer 1

I'd say there is barely enough information in the question to speculate on an answer but it sounds like to me that...

If your data is saved in individual key/value pairs then delete_post_meta will do it. You would pass the function a post ID and a key name: delete_post_meta(1,'keyname');. It will delete the whole key/value pair.

If you have multiple bits of information saved as a serialized array/object then delete_post_meta will not work. You will need to pull the data for the key you want with get_post_meta, alter the array/object in PHP to remove the key/value you want to delete, and then save the altered data with update_post_meta.

http://codex.wordpress.org/Function_Reference/get_post_meta
http://codex.wordpress.org/Function_Reference/update_post_meta