Re: [HACKERS] Challenges preventing us moving to 64 bit transactionid (XID)?

On Thu, Jul  6, 2017 at 07:29:07AM -0700, Jim Finnerty wrote:
> re: "The problem is if you want to delete from such a page.  Then you need to
> update the tuple's xmax and stick the new xid epoch somewhere."

I am coming to this very late, but wouldn't such a row be marked using
our frozen-commited fixed xid so it doesn't matter what the xid epoch is?
I realize with 64-bit xids we don't need to freeze tuples, but we could
still use a frozen-commited fixed xid, see:
#define FrozenTransactionId         ((TransactionId) 2)

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com

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