As title says, I was looking to compare User give date range with date range saved in mysql Database. I search internet and found a great  small function that solve this problem for me, though they create a function for some programming language but I use same function in mysql (as per mysql syntax) and its all done

select * from  TableName where
(‘2008-04-16’ = start_date) or
if((‘2008-04-16’ > start_date),(‘2008-04-16′<=end_date),(start_date<=’2008-08-20’))

here 2008-04-16 is user enter date, and 2008-08-20 is user end end date for date range I collect from web form, and start_date and end_date is field in my table that define date range.

you can read about function here http://ryanfarley.com/blog/archive/2004/08/19/966.aspx