Re: Re: BUG #10329: Could not read block 0 in file "base/56100265/57047884": read only 0 of 8192 bytes

On 2014-09-11 19:25:13 +0200, Stefan Kaltenbrunner wrote:
> On 09/08/2014 03:45 PM, Bruce Momjian wrote:
> > On Sat, Sep 6, 2014 at 09:42:45PM -0400, Alvaro Herrera wrote:
> >> Bruce Momjian wrote:
> >>
> >>> Here is a patch which implements the warning during CREATE INDEX ...
> >>> HASH. If WAL-logging of hash indexes is ever implemented, we can remove
> >>> this warning.
> >>
> >> I think we should have CREATE UNLOGGED INDEX, and simply disallow any
> >> hash index from being created unless it's marked as such.
> >
> > Wow, that sounds much more radical than we discussed. Seeing I got
> > push-back just for the warning, I don't see how disabling "logged" WAL
> > indexes is going to be accepted.
> >
> > It is a good idea, though. :-)
>
> I agree there - implementing CREATE UNLOGGED INDEX and use THAT for hash
> indexes seems like a fairly clean thing to me, hash indexes _are_
> unlogged so lets reflect that directly.
> I could even envision pg_dump doing that conversion automatically...

I think this did came up as a solution before. It's just that nobody
found a reasonably easy and clean way to do unlogged indexes on logged
tables so far. It's far from trivial.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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