Re: update on global temporary and unlogged tables

On Mon, Sep 13, 2010 at 9:06 PM, Rob Wultsch <wultsch(at)gmail(dot)com> wrote:
> On Mon, Sep 6, 2010 at 7:55 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>>
>> 3. With respect to unlogged tables, the major obstacle seems to be
>> figuring out a way for these to get automatically truncated at startup
>> time.
>
> (please forgive what is probably a stupid question)
> By truncate do mean reduce the table to a very small number (or zero) number
> of pages? Is there a case to be made for instead somehow marking all pages
> as available for reuse? Deallocating and reallocating space can be
> expensive.

I think it's probably actually cheaper to truncate them, but since it
only happens at startup time it's probably not worth worrying
about....

--
Robert Haas
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