The Digg link said it best: "Since it was already necessary to abandon data normalization and consistency to make these approaches work, we felt comfortable lo

The Digg link said it best: "Since it was already necessary to abandon data normalization and consistency to make these approaches work, we felt comfortable looking at more exotic, non-relational data stores" In other words, to get MySQL to superduper scale, you have to turn it into NoSQL anyway. At which point, the only reason to be using MySQL at all is inertia, because it's pretty clunky compared to the other alternatives. Back in the day before Cassandra and etc, there wasn't a concept for NoSQL, and sharding MySQL looked like an exotic way of using a relational DB. Actually, no. It's a way of crudely emulating something that isn't a relational DB.