There is another type of DBA which may or may not fit within the definition of 'Hybrid' DBA, but stands apart from the first two in terms of the requirements.
The 'Data Warehouse' DBA is required to not only forget or re-learn some of the basic principles of the other types, but also to learn quite a few new ones; for example how to deal with very large data volumes, advanced optimisation, partitioning for performance etc.
I often find the more 'traditional' DBA will not recognise these differences, and some will even argue about techniques etc. becasue they go against their established knowledge - however as Business Intelligence systems become a norm in the modern enterprise, DBA's are be called on more and more often to manage and improve on such databases.
It is worth finding out if you're about to attend an interview if the company has a data warehouse, or intends to build/buy one, as the job role may expand to include the need to fulfill this role.