Re: Unexpected chunk number

Chris Purcell wrote:
> Hi,
>
> On running pg_dump, I am consistently getting the following errors:
>
> pg_dump: ERROR: unexpected chunk number 2 (expected 0) for toast value
> 223327
> pg_dump: SQL command to dump the contents of table "pagecache" failed:
> PQendcopy() failed.
> pg_dump: Error message from server: ERROR: unexpected chunk number 2
> (expected 0) for toast value 223327
> pg_dump: The command was: COPY meatballwiki.pagecache (page,
> lastmodified, response) TO stdout;
>
> I am running psql 8.1.4. The disk storing the database was recently
> corrupted, and we restored from an old image; I appreciate this is
> likely to have triggered the error. What I'm interested in is how to fix
> it!

"old image" - does that refer to something like an filesystem level
backup or the restoration of a former pg_dump generated backup ?
The former is generally NOT save (except if you followed the
PITR-advises in the docs or similiar) with a running postmaster ...

Stefan