Tom Lane wrote:
"Florian G. Pflug" <[EMAIL PROTECTED]> writes:
Tom Lane wrote:
One thought here is that it's not clear that we really need a concept of
transaction-controlled vs not-transaction-controlled xlog records
anymore.
I've thinking about keeping XLOG_NO_TRAN, and doing
if (!no_tran)
Assert(TransactionIdIsValid(GetCurrentTransactionIdIfAny())
in xlog.c as a safety measure.
Why do you think this is a safety measure? All that it is checking
is whether the caller has preserved an entirely useless distinction.
The real correctness property is that you can't write your XID
into a heap tuple or XLOG record if you haven't acquired an XID,
but that seems nearly tautological.
I was confused. I wanted to protect against the case the an XID hits
the disk, but doesn't show up in any xl_xid field, and therefore might
be reused after crash recovery. But of course, to make that happen
you'd have to actually *store* the XID into the data you pass to
XLogInsert, which is kind of hard if you haven't asked for it first.
So, I now agree, XLOG_NO_TRAN should be buried.
greetings, Florian Pflug
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