Schemas using compact storage can have clustering keys with the trailing
components not set and effectively being a clustering key prefixes
instead of full clustering keys.
Signed-off-by: Paweł Dziepak <pdziepak@scylladb.com>
We now have partition_key_view, clustering_key_view, etc.
Database APIs will be extended to also accept views.
This will alows us to avoid allocations in certain scenarios.
