Relational model fading.
How FriendFeed uses MySQL to store schema-less data - Bret Taylor's blog: "How FriendFeed uses MySQL to store schema-less data
February 27, 2009
Background
We use MySQL for storing all of the data in FriendFeed. Our database has grown a lot as our user base has grown. We now store over 250 million entries and a bunch of other data, from comments and 'likes' to friend lists.
As our database has grown, we have tried to iteratively deal with the scaling issues that come with rapid growth. We did the typical things, like using read slaves and memcache to increase read throughput and sharding our database to improve write throughput. However, as we grew, scaling our existing features to accomodate more traffic turned out to be much less of an issue than adding new features."
