Tuesday, November 22, 2011
Replication is never a proper replacement for backups
Today I almost had that special moment that makes you glad you did backups -- was going to drop the database and noticed that I'm on the wrong server less than a second before my finger finally reached that "Enter" key =) I wonder if MongoDB should have some built-in measures against this, maybe some kind of database/collection setup versioning that prevents actual data loss. Then again, I think that's too much for a general-purpose database, but still, having some kind of schema versioning with ability to do a rollback would be a nice feature for something that is already complex and proven to be robust enough for critical applications, like PostgreSQL. Still, the (learned before) lesson for today was that you should never count on replication alone for protection, software failures (both client- and server-side) still may destroy your data.