Re: Improve warnings around CREATE INDEX CONCURRENTLY

On Thu, May 26, 2011 at 11:52 AM, Alvaro Herrera
<alvherre(at)commandprompt(dot)com> wrote:
> Excerpts from Greg Smith's message of mié may 25 17:04:03 -0400 2011:
>
>> Sure.  Simon's command string idea might work better, and doing some
>> extra lock decoration as you suggested in the above thread would be
>> another level of improvement.  We should pick up redesign later on the
>> main list.  You can at least count me in as someone who wants to see
>> this improved now.
>
> Great
>
>> Back to the doc patch I submitted...is that a useful step toward making
>> this issue visible enough to users for now to help?
>
> Sure, why not?  I thought I could choose my bikeshed color while I was
> here, how about
>
> +    second and third transaction.  All active transactions at the time the
> +    second table scan starts, not just ones that already involve the table,
> +    have the potential to block the concurrent index creation until they
> +    finish.  When checking for transactions that
> +    could still use the original index, concurrent index creation advances
> +    through potentially interfering older transactions one at a time,
> +    obtaining shared locks on their virtual transaction identifiers to wait for
> +    them to complete.

Alvaro, did you commit this?

--
Robert Haas
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