Re: Recovering data from corrupted table. Urgent Help!!

Hi Gaetano:

This procedure to recover data from a corrupted table should be
documented somewhere... If it is, I could not find it!

Now I wonder if I have lost any data, because after creating the
pg_clog/0004 and running VACCUM everything seems ok.

Thanks a lot for your help.
Ruben.

> Gaetano Mendola wrote:
>
>>ruben20@superguai.com wrote:
>>
>>
>>>Hi:
>>>
>>>Is there any way to recover data from a corrupted table? I can only
>>>run SELECTs on certain WHERE conditions.
>>>
>>>I cannot vacuum, pg_dump, I've deleted the indexes and try to reindex,
>>>always get error:
>>>
>>>ERROR:  could not access status of transaction 4244329
>>>DETAIL:  could not open file "/usr/local/pgsql/data/pg_clog/0004": No
>>>existe el fichero o el directorio
>>>
>>>Thanks a lot.
>>
>>
>>Again:
>>
>>
>>create an empty file:
>>
>># touch /usr/local/pgsql/data/pg_clog/0004
>>
>>at this point postgres will complain about the fact that an offset is
>>missing,
>>
>>at this point fill with 0 your file ( blocks of 8K ) till reach that
>>offset reclaimed.
>
>
> I forgot to suggest you to do:
>
> dd bs=8k count=1 < /dev/zero >> /usr/local/pgsql/data/pg_clog/0004
>
> you have to repeat this command till the offset is covered.
>
> Regards
> Gaetano Mendola