Re: HOT updates & REDIRECT line pointers - Mailing list pgsql-hackers

From Robert Haas
Subject Re: HOT updates & REDIRECT line pointers
Date
Msg-id CA+TgmoarcqsByWqzWExwGJ59agE0ttRDe-bcxV3DqOpjZUL5Kw@mail.gmail.com
Whole thread Raw
In response to Re: HOT updates & REDIRECT line pointers  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: HOT updates & REDIRECT line pointers  (Simon Riggs <simon@2ndQuadrant.com>)
Re: HOT updates & REDIRECT line pointers  (Merlin Moncure <mmoncure@gmail.com>)
Re: HOT updates & REDIRECT line pointers  (Pavan Deolasee <pavan.deolasee@gmail.com>)
Re: HOT updates & REDIRECT line pointers  (Bruce Momjian <bruce@momjian.us>)
List pgsql-hackers
On Wed, Mar 21, 2012 at 9:22 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> It strikes me that it likely wouldn't be any
>> worse than, oh, say, flipping the default value of
>> standard_conforming_strings,
>
> Really?  It's taking away functionality and not supplying any substitute
> (or at least you did not propose any).  In fact, you didn't even suggest
> exactly how you propose to not break joined UPDATE/DELETE.

Oh, hmm, interesting.  I had been thinking that you were talking about
a case where *user code* was relying on the semantics of the TID,
which has always struck me as an implementation detail that users
probably shouldn't get too attached to.  But now I see that you're
talking about something much more basic - the fundamental
implementation of UPDATE and DELETE relies on the TID not changing
under them.  That pretty much kills this idea dead in the water.

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


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