Re: ERROR: missing chunk number 0 for toast value - Mailing list pgsql-hackers

From Andres Freund
Subject Re: ERROR: missing chunk number 0 for toast value
Date
Msg-id 20140106144704.GI28320@alap2.anarazel.de
Whole thread Raw
In response to Re: ERROR: missing chunk number 0 for toast value  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: ERROR: missing chunk number 0 for toast value  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On 2014-01-06 09:43:45 -0500, Robert Haas wrote:
> > I actually vote for not allowing doing so at all by erroring out when
> > accessing a plpgsql variable created in an aborted subxact, unless you
> > explicitly signal that you want to do do so by calling some function
> > deleting the information about which subxact a variable was created
> > in. I have seen several bugs caused by people assuming that EXCEPTION
> > BLOCK/subtransaction rollback had some kind of effects on variables
> > created in them. And we just don't have much support for doing anything
> > in that direction safely.
> 
> So, you want to let users do things that are unsafe, but only if they
> ask nicely?  That hardly seems right.

Well, no. If they have to use that function explicitly *before* the
subxact aborted, we can copy & detoast the value out of that context
safely.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services



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