Adding days to a date can be done like this:
The following code adds 7days to the current date.
GeSHi (sql):
SELECT top 1 getdate() AS currentDate, dateadd(d,7,getDate()) AS newDate FROM tblName
Created by GeSHI 1.0.7.20
Output:Current date New date
2010-02-22 14:27:31.280 2010-03-01 14:27:31.280
Removing days is just a simple:
GeSHi (sql):
SELECT top 1 getdate() AS currentDate, dateadd(d,-7,getDate()) AS newDate FROM tblName
Created by GeSHI 1.0.7.20
Output:Current date New date
2010-02-22 14:30:04.137 2010-02-15 14:30:04.137