One thing that's sorely needed in the official documentation is a "best practice" for backup/restore from "cold and dark" where you lose your main db in a fire and are now restoring from offsite backups for business continuity. Particularly in the 100-2TB range where probably most businesses lie, and backup/restore can take anywhere from 6 to 72 hours, often in less than ideal conditions. Like many things with SQL there's many ways to do it, but an official roadmap for order of operations would be very useful for backup/restore of roles/permissions, schema etc. You will figure it out eventually, but in my experience the dev and prod db size delta is so large many things that "just work" in the sub-1gb scale really trip you up over 200-500gb. Finding out you did one step out of order (manually, or badly written script) halfway through the restore process can mean hours and hours of rework. Heaven help you if you didn't start a screen session on your EC2 instance when you logged in.
Offsite replica is only applicable if the cause is a failure of the primary. What if I’m restoring a backup because someone accidentally dropped the wrong table?
nah, on a long enough timeline everything will go wrong. blaming the person who managed to drop the table finally is dumb: if you can't fix literally everything that could happen to it, it's not done.
Of course that’s preferable, but OP is specifically asking about the cold restore case, which tends to pose different problems, and is just as important to maintain and test.
If you can have a secondary database (at another site or on the cloud) being updated with streaming replication, you can switch over very quickly and with little fuss.
Which is what you must do if minimizing downtime is critical.
And, of course, your disaster recovery plan is incomplete until you've tested it (at scale). You don't want to be looking up Postgres documentation when you need to restore from a cold backup, you want to be following the checklist you have in your recovery plan and already verified.
> in the 100-2TB range where probably most businesses lie
Assuming you mean that range to start at 100GB, I've worked with databases that size multiple times but as a freelancer it's definitely not been "most" businesses in that range.
Postgres backups are tricky for sure. Even if you have a DR plan you should assume your incremental backups are no good and you need to restore the whole thing from scratch. That’s your real DR SLA.
If things go truly south, just hope you have a read replica you can use as your new master. Most SLAs are not written with 72h+ of downtime. Have you tried the nuclear recovery plan, from scratch? Does it work?
While these optimizations are solid improvements, I was hoping to see more advanced techniques beyond the standard bulk insert and deferred constraint patterns. These are well-established PostgreSQL best practices - would love to see how pgstream handles more complex scenarios like parallel workers with partition-aware loading, or custom compression strategies for specific data types.
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