Oh, database backups are fun, especially if the database server is still running! You want multiple databases, all at a consistent point in time, without taking the system offline? SUFFER, YOU FOOL! The joys of realizing that file system snapshots won't help with data that's still to be committed and that taking a backup database-by-database means that two databases whose data relies on each other are no longer properly in sync really warms my heart. Oh wait, it's the whiskey that runs through my veins that does that, being a backup operator is a fantastic pathway into alcoholism. Especially once the databases become so large, that the time it takes to take the backup become a performance concern of the running system.
I think Postgres did it right by abbreviating their "Continuous Archiving and Point-in-Time Recovery" as PITR because it's very close to PITA. But PITR and CHECKPOINT actually make Postgres probably one of the better database systems to backup (and restore!), so yet another reason why I think it's a fantastic database.
