ACF relationship fields saving with Pro Form

Miscellaneous
1

Hello,
I’m using Pro Form to create post on frontend and I have relationship field with another post type - I’ve created function which returns post_id|post_title and user can choose from select field. Everything works as expected, I’ve just found a little problem.
ACF saves relational field as serialized array (example: * a:2:{i:0;s:2:”35″;}), in my function is just post_id, so frontend form saves post_id only (example: 35). When querying this relation field, serialized array needs this arg:

'meta_query' => array(
                                array(
                                    'key' => 'contractor', // name of custom field
                                    'value' => '"' . $post_id . '"', // matches exactly "35", not just 35. This prevents a match for "356"
                                    'compare' => 'LIKE'
                                )
                            )

and post_id this arg:

'meta_query' => array(
                                array(
                                    'key' => 'contractor', // name of custom field
                                    'value' =>  $post_id, // 35
                                    'compare' => '='
                                )
                            )

this is link to acf documentation

In my case, all posts are created with frontend form (and won’t be created in backend) and in query loops when using ‘compare’ => ‘=’, everything works as expected and I didn’t encounter any issues. But I really don’t know if this is right approach or if I’m creating problem for the future…
It’s just a small invoice creation project for my personal use - I wanted to learn more about wordpress - I’m self learner and not really experienced yet and I would like to ask your opinion Daniele (or anyone else). Thank you very much in advance.

2

Did you ever find a solution to this? I have a select element populated from a related table. When i select one or more entries from the sekect, it seems to update the back end, however if i open the post again on the front end, none of the select options are selected.
Many thanks
Pete

3

It works with just the post_id on my side. If it updates the backend, try clearing the cache in plugins and on the server side.

4

In your post meta submit action, did you remember to use :array in the form field? And what is the update type you’re using?

5

Yes