Re: Unlogged tables, persistent kind

On Sun, Apr 24, 2011 at 7:41 PM, Greg Stark <gsstark@mit.edu> wrote:
> On Sun, Apr 24, 2011 at 6:22 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
>> My implementation path for that would be to add a crash_number onto
>> pg_control and pg_index. Any index marked as "unlogged, persistent"
>> would only be usable if it's crash number is the same as current
>> system crash number.
>>
>> REINDEX would update the index crash number to current value. That
>> also allows us to imagine a "repair index" command in the future as
>> well.
>
> This seems useful for non-crash-safe indexes in general.
>
>> Heap blocks would be zeroed if they were found to be damaged, following a crash.
>>
>
> How do you propose to detect that? Until we solve the whole checksum
> story I don't think we have a reliable way to detect bad pages. And in
> some cases where do detect them we would detect them by crashing.


That should be changed.


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