Filter by subquery?

Hi diekunstderfuge,

Thanks for the great use-case. I don’t have a perfect solution for you, but in the version 1.5.31 I added something that can help. A new callback filter.

So you can add a new filter and use a callback to alter the query arguments before the query is built. Couple that with the codex on a date_query ( https://codex.www.ads-software.com/Class_Reference/WP_Query#Date_Parameters ) and it shouldn’t be too hard to achieve.

Something like this should theoretically work.

function my_custom_filter_callback($args, $filter){
	$after = explode('-', '2015-01-25');
	$before = explode('-', '2015-12-01');

	$args['date_query'] = array(
		'after' => array(
			'year' => $after[0],
			'month' => $after[1],
			'day' => $after[2],
		),
		'before' => array(
			'year' => $before[0],
			'month' => $before[1],
			'day' => $before[2],
		)
	);

  return $args;
}

Let me know how this goes. I’ll look into adding a date_query field in the future.

Thanks,
Jonathan

Quick follow up:

I also added functionality to the “Post IDs” filter. It can now accept an array of post ids returned from a callback.

Again, while this is not ideal, it should drastically increase your options for getting the results you want.

Hi Jonathan,

Thanks for your reply! Your code certainly works, but I’m a little unclear on where in the filter/callback to specify that it is a specific ACF field, i.e., meta_keyname, to which the callback should apply. In other words, how do I make sure it is the value of my custom field that falls between $before and $after, and not another WP date field, like post creation date or publish date? Do I need to do something with the $filter argument? Forgive me, I’m still getting used to WP development!

Thanks again!

Hi diekunstderfuge,

Ah, sorry, I wasn’t thinking right. You need a meta_query: https://codex.www.ads-software.com/Class_Reference/WP_Query#Custom_Field_Parameters

function my_custom_meta_query_filter_callback($args, $filter){

	$args['meta_query'] = array(
		array(
			'key' => '_my_custom_field',
			'type' => 'DATE',
			'compare' => 'BETWEEN',
			'value' => array('2015-01-25', '2015-12-01')
		),
	);

	return $args;
}

That should work for you, but note that the codex says: “The ‘type’ DATE works with the ‘compare’ value BETWEEN only if the date is stored at the format YYYY-MM-DD and tested with this format.”

Let me know how it goes!

Thanks,
Jonathan

Yes, that works, and thank you for pointing out that disclaimer in the codex; I immediately saw that ACF was storing my dates as YYYYMMDD instead of YYYY-MM-DD and I probably would have spent much longer hunting for the source of the problem.

Thanks again for your help!

Cheers!