Re: simple_heap_update: tuple concurrently updated -- during INSERT

Dear Tom,

I'll try my best. Also, I'll try to describe the situation more precisely,
in case it may give you another idea.

INSERT INTO p_items;
-> p_items before: INSERT, UPDATE and/or DELETE other tuples in p_items
-> p_items after: UPDATE p SET touch_time, toucher;
----> p after: INSERT INTO p_ny
-------> p_ny after: NOTIFY p

May it be that more "NOTIFY p"'s come from the same transaction (since I
change more than one tuples in p_items)? Based on the error text, I assume
this error comes only when two different transactions clash.

I think it's very unlikely anyway since it happens ~100-1000 times a day and
so far (~2 years of 7.3.3) this is the only occurence of this error.

A final question: as far as you can remember, may this be an issue already
fixed in later versions?

Thanks again, HTH, and I'll report back if I encounter the error again.
G.
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----- Original Message -----
From: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Subject: Re: [HACKERS] simple_heap_update: tuple concurrently updated --
during INSERT

> "=?iso-8859-2?B?U1rbQ1MgR+Fib3I=?=" <surrano(at)mailbox(dot)hu> writes:
> > Q1. So is this everything that can be said -- NOTIFY calls
> > simple_heap_update that is concurrently updated by a different
transaction?
>
> If that's what it is, then there's still a question: why? The notify
> code has enough locking that this failure shouldn't happen. If you can
> reproduce this I'd like to look into it.
>
> regards, tom lane
>