Re: GetTransactionSnapshot() in enum.c - Mailing list pgsql-hackers

From Robert Haas
Subject Re: GetTransactionSnapshot() in enum.c
Date
Msg-id CA+Tgmobzt30UE6uM4bO4=A-R9yJwW8tj7QiSwPEKVoLhquTn9Q@mail.gmail.com
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In response to Re: GetTransactionSnapshot() in enum.c  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Mon, Aug 26, 2013 at 4:31 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Mon, Aug 19, 2013 at 1:41 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> BTW, I notice that the MVCC-catalog-scans patch summarily asserts that
>>> RenumberEnumType no longer poses any concurrency hazards.  I doubt that's
>>> true: isn't it still possible that pg_enum rows acquired through the
>>> syscaches will have inconsistent enumsortorder values, if they were
>>> read at different times?  If you want to examine enumsortorder, you really
>>> need to be comparing rows you know were read with the *same* snapshot.
>
>> Good point, I missed that.  Here's a proposed comment patch.
>
> Looks sane to me.

Thanks for the review.  Committed.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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