OK, easier with picture :
1/ you create your date database, as long as you wish, in my example i can also check if the date is a monday or whatever
2/ You create your main database with begin date, end date. I suggest each date is a lookup to the Date database
Then, if you want a end date greater than begin, just make the lookup and add custom filter
Another use case : if you want to select only monday, just filter where DayNumber=1
Then you can custom the range as much as you need !
Is that clearer ?
Quentin