Sometimes when i’m developing a membership site i need to test assigning a post author if the code was not right the first time its good to be able to remove the author rather than having to start a new test.
<?php $arg = array( 'ID' => 8378, //or whatever the post id is 'post_author' => "", ); wp_update_post( $arg );
Simply add the above to the functions.php open any page to run and then delete.