From: http://run-node.com/littlest-database-that-could/
I've written numerous tiny databases. They don't have much features, but they don't need much features. Usually I'm looking for fast simple key/value stores and Node never disappoints. The point here is, why abstract key value store when JS gives us one for free, as it's most basic component: object.
Will it meet every need? No. But it will meet ALOT of scenarios.
In memory JS object lookups, were talking hundreds of thousands of lookups (you'll easily flood http before the db), and save hundreds of thousands of records in a JSON file written to disk. Not a 200ms r/t to some hosted Redis. Hey, that's fine if that's your thing.
Here's the requirements: