CouchDB - blessings and curses
John Wood (of Signal fame) has a post up about Signal's experience moving to, and away from, CouchDB. Its an interesting real-world example of what I've described in " NoSQL - What you'll find (for sure!) ". To recap, when first getting into NoSQL, you are sure to find that You didn't understand your own problem-space as well as you thought you did. You didn't understand the package that you are using as well as you think you do. It will not scale the way you thought it would. Oh, it'll scale all right, just not the way you thought it would. Your object/document/JSON/whatever model really doesn't map exactly the way you expected it to. In John's case, they found that HTTP is a Very Slow Database Protocol MVCC Overhead (is bad) Large Databases Beat Up the Hard Disk CouchDB is not a Distributed Database (by default) map/reduce takes a while to get used to Views take forever to build Views are gigantic on disk Replicati...