will wp_insert_post write a new custom field to the database?

Question

If i use wp_insert_post like that:

wp_insert_post(array('post_title' => 'some title', 'post_status' => 'draft', 'meta_input' => array( '_pf_mainphone' => $pro_phone ),'tax_input' => array( 'places_taxonomy' => $_POST["npf_newpro_places"], 'protags' => $_POST["npf_newpro_tags"],)));

And let's suppose that the _pf_mainphone isn't a real custom field (there isn't such a custom field in my installation / setup...).

The Question is will it write something to database or will it just ignore this part of the code?

The Reason i ask this (although i think it's not really necessary for answering the question) is:

I want to code a function that will that will take each field in a long form and set it's value to be the value of custom field with the same name as the field's name attribute, and there are 2 (out of 34) fields that don't exists as custom fields (i use another function for another purpose with them...).

Answer 1

Yes, wp_insert_post() will automatically insert new postmeta as well.

I just tried out your exact code and it worked. And the reason behind this could be quite simple: In WordPress, meta info for a post is only a key and value pair. There is no strict rule that keys have to be defined somewhere, so you can easily insert your own at any given moment.