truncating data older than 30 days

Hi,
I have a table with
C1- ID
C2-Date
C3-Date with time
C4-quantity
I need to create a daily process that will remove the oldest data(data older than 30 days) on the table and make sure the table is with only 30 days worth of data.
Please help me.
Thanks in advance

DELETE Table WHERE C3 < Datediff(dd, 30, Getdate())

You can set up a job that runs every night and cleans up the data.

If you have stored insertdate in c3 column then the query should be
delete yourtable where c3<dateadd(dd,-30,getdate())
This query will check recordsdate which are less than 30 days old and will delete it. Also as suggested put this query as a agent job and schedule it to run midnight.