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Re: using custom scan nodes to prototype parallel sequential scan - Mailing list pgsql-hackers

From David Rowley
Subject Re: using custom scan nodes to prototype parallel sequential scan
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Msg-id CAApHDvr2Nx+tHW+YBR1ON+Qp87eros0nN5skNwiHBy21GJSvgA@mail.gmail.com
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In response to Re: using custom scan nodes to prototype parallel sequential scan  (Simon Riggs <simon@2ndQuadrant.com>)
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On Fri, Nov 14, 2014 at 1:27 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
On 12 November 2014 00:54, Robert Haas <robertmhaas@gmail.com> wrote:
> Interestingly, I have a fairly solid idea of what proisparallel is,
> but I have no clear idea what CONTAINS NO SQL is or why it's relevant.
> I would imagine that srandom() contains no SQL under any reasonable
> definition of what that means, but it ain't parallel-safe.

What is wrong in generating random numbers in parallel?

I was just watching Robert's talk on Parallel query on youtube... I think the answer is at 41:09, the link below should take you there:

Regards

David Rowley

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