We use `data_resource` class in the CQL parser, which let's users refer to a table resource without specifying a keyspace. This asserts out in get_level() for no good reason as we already know the intented level based on the constructor. Therefore, change `data_resource` to track the level like upstream Cassandra does and use that. Fixes #1790 Message-Id: <1477599169-2945-1-git-send-email-penberg@scylladb.com>