Re: pgsql: Implement ALTER TABLE .. SET LOGGED / UNLOGGED

On 23 August 2014 14:57, Andres Freund <andres(at)anarazel(dot)de> wrote:
> On August 23, 2014 3:49:32 PM CEST, Simon Riggs <simon(at)2ndQuadrant(dot)com> wrote:
>>On 22 August 2014 19:30, Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
>>wrote:
>>
>>> Implement ALTER TABLE .. SET LOGGED / UNLOGGED
>>>

>>When moving from unlogged to logged, where do we remove the init fork?
>>
>>Couldn't see the keywords fork or init anywhere in the patch, so maybe
>>its hidden somewhere.
>
> A new relfilenode is filled with the data - the old one, including the init fork, gets removed by the normal mechanics of rewriting rels.

Why do we do that? Table rewrite takes hours.

If that is a requirement, I don't see it documented. If its a choice,
its a bad one.

--
Simon Riggs http://www.2ndQuadrant.com/
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