While rummaging around on the internet the other day, I came across this interesting depiction of the current state of database software. It's an "infographic", inspired by subway maps like the famous London Underground map, attempting to relate a long list of database implementations of various types.
My great friend Walt used to say that "any field of study can always be infinitely sub-divided". There are many, many ways to slice the pie, and many, many different ways to build database software.
I've been working in the database field for 30 years now, and it never gets stale. The old ideas continue to bear up under study and refinement, and as new ideas come along, they are incorporated into the mix. We "high priests of a low cult" continue to beaver away at the details, and the world of database software incrementally becomes more sophisticated, more complex, and more powerful.
I'm familiar with about a third of the database systems described on the map, which means I've still got a lot to learn! Of course, to keep abreast of all of this activity, you'd really have to make it a full time job, like the 451 guys do, or like somebody like Curt Monash does, and I don't do that (I'm a systems builder, not an industry analyst, after all).
But I'm looking forward to following up on some of these references and learning more about parts of my field that I wasn't even aware of.