select regexp_replace('Download file:/webdocs/data/groupXXX/case/03_28_54_9_0000011856.pdf',
'.*/([^/]+)/[^/]*$', '\1') from dual;
select regexp_replace('Download file:/webdocs/data/groupXXX/case/03_28_54_9_0000011856.pdf',
'.*/([^/]+)/[^/]*$', '\1') from dual;