- var_dump: documentation ( source)
- substr_replace: documentation ( source)
<?php
$str = '
SELECT picture.`%1$s` AS entity_id, picture.picture_id
FROM picture
JOIN category_pictures USING (picture_id)
WHERE picture.`%1$s` IN (%2$s)
#FILTER_CATEGORY AND category_pictures.category_id IN (%3$s)
';
var_dump(substr_replace($str, '', 207, 16));