SUP - 2 questions about the CDB (cache database)

Hi,

I have 2 questions about the cache database and the cache groups:

1 - How does the "On demand" cache group policy exactly works? I know that online cache group is without storing any data on the CDB making direct requests to de backend from the device, the DCN is based on updating from the backend, the scheduled is based on a time period, but I don't understand how the "on demand" exactly works, and why it has a time period too.

2 - Is it possible to query the cache database table to check the data that SUP has stored? How can I do this?

Thank you!