[breischl]

NoSQL DBs definitely have their place. For instance my current project uses one to handle and do limited querying on data from other systems without needing to have a full schema for that data. You could do it in SQL by breaking out the columns we need and storing the rest in an XML blob, but it would be annoying. One rule of thumb might be that anytime you want to stick an XML blob into SQL, consider NoSQL instead.

That said, I think you're right that 90% of the time SQL is a better solution. You don't fully realize all the great stuff a real SQL engine does for you until you have to go without it.