Sort posts in a widget using 2 ACFs

• Risk-Averse-Rider

• February 23, 2023 at 5:47 pm

I have a field group for standard WP posts that includes among others) the following optional ACFs:

• start_date – set using the Date Picker
• start_time – set using the Time Picker; only available if start_date has a value

To be clear: not all the posts that have start_date value also have a start_time value.

I have custom widget that only displays posts that have a start_date value that’s (1) today or later, and (2) that’s within the next N days, where N is set in the widget admin interface. The posts are sorted by start_date in ascending order.

That part all works just fine. Where I’m having trouble is being able to include the optional start_time ACF in the sort order so that posts would be listed like this:

February 23
February 24 10:00am
February 26
March 5 8:00am
March 5 10:00am
March 6

This is the $args array that sorts (correctly) only by start_date:

    $args = array(
      'ignore_sticky_posts'=> 0,
      'post_type' => 'post',
      'post_status' => 'publish',
        'meta_query' => array(
          array(
            'key' => 'start_date', // ACF field for event start date
            'value' => date('Ymd', strtotime("+{$nr_days_ahead} days")), // restrict start date to no more than today + $nr_days_ahead
            'compare' => '<=',
            'type' => 'DATE'
          ),
          array(
            'key' => 'start_date', // ACF field for event start date
            'value' => $today,
            'compare' => '>=',
            'type' => 'DATE'
            )
          ),
      'posts_per_page' => $nr_posts,
      'cat' => $categories,
      'meta_key' => 'start_date',
      'orderby' => 'meta_value_num',
      'order' => 'ASC'
    );

I spent quite a bit of time today with ChatGPT (just in case anyone feels like suggesting that approach), but never got anywhere (other than a couple critical errors that brought the site down, but I can manage that all by myself).

Any suggestions?

• John Huebner

• February 26, 2023 at 11:03 am

Some issues with your current code.

ACF does not store date fields in the DB as dates. It saves strings that are in the format of ‘Ymd’, so using a type of “DATE” will produce errors.

If you want to sort by the second field then that field must have a value in the DB (even if that value is an empty string). WP will ignore any posts that do not have a value set for a field. I’m not sure what you mean by optional, but in this case the field would always need to be visible and allow no input.