Here’s a quick list (mostly for myself) of RDBMSes I want to check out:
Open Source
CUBRID | PostgreSQL | CouchDB (NoSQL)
Commercial
Hyperion | Teradata | Vertica | Netezza | ParAccel | AsterData
Mixed Licensed
There’s certainly more to this, and it may seem that I’ve overlooked things in my experience, but this is about deeper dives and figuring out what makes each tick and more importantly, how they’re differentiated. CUBRID is currently my fancy, but the documentation is very abstruse since it’s global release early last month.