Even if you didn't think that the business intelligence market was a mature market, I am sure that most of you think that the database market is completely done and dusted. Well, not in my experience. There are more different types of commercial database available today, than there have ever been.
A decade ago there were the remnants of the navigational/hierarchical databases still with us (and they remain so today), there were relational databases that already ruled the roost, there were the up-and-coming (and soon to be shot down) object databases, there were what we used to call post-relational databases (those that use NF2 - non-first normal form) such as Unidata and UniVerse (both now a part of IBM since its acquisition of Informix), and there were the newly introduced OLAP databases.
Today, all of these database types are still in use although most (though not all) of the object databases have been reused as something else.
Now consider what has been added to this list. Perhaps the first of the new style databases to appear was ...
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