Suppose I have a snapshot created like the one below. How do I then refresh it on a daily basis. I am confused on the NEXT clause of the create snapshot command. I basically want to referesh it not only on 9/20/2002 but also on 9/21, 9/22 etc...

Also, if I use REFRESH FORCE method does it refreshes the data that is not changed in 'some_table' or the entire table is brought over on to 'snap'.


CREATE SNAPSHOT snap

NOLOGGING
NOCACHE

REFRESH FORCE
START WITH TO_DATE('19-Sep-2002','DD-MON-YYYY')
NEXT TO_DATE('20-Sep-2002','DD-MON-YYYY')
WITH PRIMARY KEY
USING DEFAULT ROLLBACK SEGMENT
DISABLE QUERY REWRITE AS
select day, count(column1), count(column3)
from some_table
group by day
;