Re: switch UNLOGGED to LOGGED

On Sat, Apr 9, 2011 at 3:29 AM, Leonardo Francalanci <m_lists@yahoo.it> wrote:
>> I'm pretty sure we wouldn't accept a patch for a  feature that would
>> only work with wal_level=minimal, but it might be a useful  starting
>> point for someone else to keep hacking on.
>
> I understand.
>
> Reading your post at
> http://archives.postgresql.org/pgsql-hackers/2011-01/msg00315.php
> I thought I got the part:
>
> "what happens if we *crash* without writing an abort record?  It
> seems  like that could leave a stray file around on a standby,
> because the  current code only cleans things up on the standby
> at the start of  recovery"
>
> But re-reading it, I don't understand: what's the difference in creating
> a new "regular" table and crashing before emitting the abort record,
> and converting an unlogged table to logged and crashing before
> emitting the abort record? How do the standby servers handle a
> "CREATE TABLE" followed by a ROLLBACK if the master crashes
> before writing the abort record? I thought that too would "leave a
> stray file around on a standby".

I've been thinking about the same thing.  And AFAICS, your analysis is
correct, though there may be some angle to it I'm not seeing.

--
Robert Haas
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