In partition definition filegroup name appears twice, what does that mean? short question regarding partitions, consider the following partition definition:

CREATE PARTITION SCHEME [MSAppServerPS_ASWcfEventsTable] AS 
PARTITION [MSAppServerPF_ASWcfEventsTable] TO ([PRIMARY], [PRIMARY])
GO


From reading about this here I understand, that this will create the partition on the socalled primary filegroup. Unfortunately in the examples on that page I did not see one example that used the same filegroup name twice.

Can someone explain to me what that means?
A partition scheme works with a partition function.

you start by creating the function where you will define the range. then the partition scheme will tell you where to store the data according to that range.

Or, to say it in another way, that particular partition scheme is just stating that for values that fall under the first condition store it in the PRIMARY filegroup, and for values that fall into the the second condition use the PRIMARY FILEGROUP.

you'll sometime see it in examples as CREATE PARTITION ... ALL TO ([PRIMARY])

Hope this helps