Matching Date in Sed: A Filename comparison example....

$ echo "01_hello_world_filename_22-07-2010.csv" | sed 's/^\([0-9]\{2\}\)\(_hello_world_filename_\)\(0[1-9]\|[12][0-9]\|3[01]\)-\(0[1-9]\|1[012]\)-\(19\|20\)[0-9]\{2\}.Csv$/Matched/ig'

Output: Matched