On 08/31/2018 08:51 AM, Dave Peticolas wrote:
On Fri, Aug 31, 2018 at 8:14 AM Adrian Klaver <adrian.klaver@xxxxxxxxxxx
<mailto:adrian.klaver@xxxxxxxxxxx>> wrote:
On 08/31/2018 08:02 AM, Dave Peticolas wrote:
> Hello, I'm running into the following error running a large query
on a
> database restored from WAL replay:
>
> could not access status of transaction 330569126
> DETAIL: Could not open file "pg_clog/0C68": No such file or directory
Postgres version?
Right! Sorry, that original email didn't have a lot of info. This is
9.6.9 restoring a backup from 9.6.8.
Where is the replay coming from?
From a snapshot and WAL files stored in Amazon S3.
Seems the process is not creating a consistent backup.
How are they being generated?
Are you sure you are not working across versions?
I am sure, they are all 9.6.
If not do pg_clog/ and 0C68 actually exist?
pg_clog definitely exists, but 0C68 does not. I think I have
subsequently found the precise row in the specific table that seems to
be the problem. Specifically I can select * from TABLE where id = BADID
- 1 or id = BADID + 1 and the query returns. I get the error if I select
the row with the bad ID.
Now what I'm not sure of is how to fix.
One thing I can think of is to rebuild from a later version of your S3
data and see if it has all the necessary files.
There is also pg_resetxlog:
https://www.postgresql.org/docs/9.6/static/app-pgresetxlog.html
I have not used it, so I can not offer much in the way of tips. Just
from reading the docs I would suggest stopping the server and then
creating a backup of $PG_DATA(if possible) before using pg_resetxlog.
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
