"Hiroshi Inoue" <Inoue@tpf.co.jp> writes:
>>>> I vacuumed here and it worked. I did not use my "old" pg_log file - what
>>>> did I lose?
>>
>> Hard to tell. Any tuples that weren't already marked on disk as "known
>> committed" have probably gone missing, because their originating
>> transaction IDs likely won't be shown as committed in the new pg_log.
>> So I'd look for missing tuples from recent transactions in the old DB.
>>
> Hmm,this may be more serious.
> MVCC doesn't see committed(marked HEAP_XMIN_COMMITTED) but
> not yet committed(t_xmin > CurrentTransactionId) tuples.
> He will see them in the future.
But he did a vacuum --- won't that get rid of any tuples that aren't
currently considered committed?
regards, tom lane