"Marc Mitchell" <marcm@eisolution.com> writes:
> This is follow-up to a problem first reported on 3/1/04. The problem
> has continued to occur intermittently and recently we experienced the
> first occurrence where the first column of a table was the column where
> the corrupted and thus we could not recover it.
It would be useful to look at pg_filedump output for the affected pages.
See http://sources.redhat.com/rhdb/utilities.html to get that program.
I find "-i -f" options to be its most useful display format, although
the raw hex dump (-d) is also good to look at when investigating
data corruption. The first part of the TID (15 in your latest example)
is the block number within the table file; you can use contrib/oid2name
if you need help figuring out which file is the table you want.
> We've observed nothing that would lead us to believe there are any
> hardware problems.
Have you done anything to proactively test for hardware problems?
memtest86, badblocks, etc? It's possible you have a software problem,
but the symptoms sound more like hardware glitches to me.
regards, tom lane