Re: Recovery target 'immediate'

On Fri, Apr 26, 2013 at 1:47 PM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On 26 April 2013 11:29, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com> wrote:
>
>> But there is also an operation to simply "restore a backup".
>
> Just because a tool supports an imprecise definition of a restore,
> doesn't mean Postgres should encourage and support that.
>
> "Restore a backup" is more suited to filesystems where most files
> don't change much. And its also a common user complaint: "I restored
> my back but now I've lost my changes. Can you help?". That's not
> something that's been heard around here because we don't encourage
> foot-guns.

I think it makes perfect sense to have this. Since we do guarantee it
to still be consistent even if things *are* changing around. The lack
of an easy way to do this is probably the most common reason I've seen
for people using pg_dump instead of physical backups in the past.
pg_basebackup fixed it for the backup side of things, with the -x
option. This appears to be a suggestion to do that kind of restore
even if you have a log archive style backups.

That said, maybe the easier choice for a *system* (such as v-thingy)
would be to simply to the full backup using pg_basebackup -x (or
similar), therefor not needing the log archive at all when restoring.
Yes, it makes the base backup slightly larger, but also much
simpler... As a bonus, your base backup would still work if you hosed
your log archive.

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/