When using SQL to find items in a call number range, best results are achieved by using cn_sort values rather than itemcallnumber values. However, most users won't know how to manually generate a padded call number for comparison to cn_sort values. It'd be helpful if we could set a runtime parameter that would allow a user to input an unpadded call number and select a classification scheme so Koha could then pad their call number and compare it to cn_sort.