Ever want to make some temporary changes to a (test) database, that you can't do with just commits? I can't remember why I needed this, but it looks handy.
#!/bin/bash # This was to create a quick snapshot of the database, make the changes I # wanted, and then revert the database to exactly the way it was before I # snapshotted it. /etc/init.d/postgresql stop umount /var/lib/postgresql/ lvcreate --snapshot --size 1G --name postgres-snap /dev/vg0/postgres mount /dev/vg0/postgres-snap /var/lib/postgresql/ /etc/init.d/postgresql start read -p "Press enter to start watching. And then ^C to drop the snapshot and switch to the old database" zzz watch lvs /etc/init.d/postgresql stop umount /dev/vg0/postgres-snap && /sbin/lvremove --force /dev/vg0/postgres-snap mount /var/lib/postgresql/ /etc/init.d/postgresql start