There isn’t any way to do a query based on the last row of a repeater field. In order to do that you would need to have the same number of rows in every repeater and you’d need to replace the % in the query with the row number. For example, if a post has 5 rows the you’d query for ‘record_4_date_in’.
Querying by and ordering by repeater sub fields is always problematic and inconsistent. Rather than try to do this I’ve found that creating a consistent field that can be used is a better solutions. For example, lets say that you want to sort your posts by the last date_in sub field.
add_filter('acf/update_value/name=record', 'my_create_a_usable_field', 10, 3);
function my_create_a_usable_field($value, $post_id, $field) {
// $value will hold a nested array with the rows of the repeater
if (!is_array($value)) {
// the repeater is empty, bail early
return $value;
}
$last_row = end($value);
$date_in = $last_row['date_in'];
// now put it into a different field
// this field can be used in queries for filtering and sorting
update_post_meta($post_id, 'filterable_date_in', $date_in);
}
Please not that you may need to do more with the value, for example, converting it into correct MySQL date format. I’m not sure what the value of a date field will be at this point. At any rate, this is a little more work, but gives you what is needed in a form that’s usable.
