// grab a snapshot of post IDs, just in case it changes during the export
$post_ids = $wpdb->get_col( "SELECT ID FROM $wpdb->posts $where ORDER BY post_date_gmt ASC" );
// grab a snapshot of post IDs, just in case it changes during the export
$post_ids = $wpdb->get_col( "SELECT ID FROM $wpdb->posts $where ORDER BY post_date_gmt ASC" );