
The most proeminent example is probably PostgreSQL, which is an incredibly strong product with high SQL power. But as soon as you access it through the ActiveRecord or Persistent API, it gets turned into a very limited store, with the SQL power of SQLITE or MongoDB.
Tom> "Limited" /= "Worst", though [0]. Tom> The popularity of SQLite and "NoSQL" prove that sometimes a limited Tom> feature set is worth the gains in abstraction. Tom> Definitely not for every project, of course. I don't dismiss MongoDB nor SQLite, they are great. But you probably don't want to limit MongoDB to a SQL features set, and you don't want to limit SQLite to a "NoSQL" interface, and you don't want to limit PostgreSQL to a SQLite features set ... As you said, each of these stores has strenghs for particular needs and weaknesses for others. Pick the one that best suits your project, and use its full power, raw :) -- Paul