ITAGAKI Takahiro <[EMAIL PROTECTED]> writes: > Tom Lane <[EMAIL PROTECTED]> wrote: >> I said nothing about expired tuples. The point of not freezing is to >> preserve information about the insertion time of live tuples.
> I don't know what good it will do -- for debugging? Exactly. As an example, I've been chasing offline a report from Merlin Moncure about duplicate entries in a unique index; I still don't know what exactly is going on there, but the availability of knowledge about which transactions inserted which entries has been really helpful. If we had a system designed to freeze tuples as soon as possible, that info would have been gone forever pretty soon after the problem happened. I don't say that this behavior can never be acceptable, but you need much more than a marginal performance improvement to convince me that it's worth the loss of forensic information. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend