Okay, I found the problem by debugging the query.
It was a generic LEFT JOIN
added with the posts_join
filter that has not alias the $wpdb->postmeta
table which finally leads to the error.
So the sorting is working now without problems.
Okay, I found the problem by debugging the query.
It was a generic LEFT JOIN
added with the posts_join
filter that has not alias the $wpdb->postmeta
table which finally leads to the error.
So the sorting is working now without problems.