in reply to Compare two dates
As others wrote, with the date-format chosen by you, you just have to apply normal string compare operators.
However in case you have other date formats (e.g. the format DD.MM.YYYY, which is popular in Germany), this approach won't work.
I made good experience in converting the date into a number (e.g. DD + 100*MM + 10000*(YYYY-2000) ), and then comparing them.