Re: COPY FROM WHEN condition

On 11/30/18 2:00 PM, Surafel Temesgen wrote:
>
>
> On Thu, Nov 29, 2018 at 2:17 AM Tomas Vondra
> <tomas(dot)vondra(at)2ndquadrant(dot)com <mailto:tomas(dot)vondra(at)2ndquadrant(dot)com>> wrote:
>
> (c) allow VOLATILE functions in the FILTER clause, but change the
> behavior to make the behavior sane
>
>  Did changing the behavior means getting new snapshot before evaluating
> a tuple to ensure the function sees results of any previously executed
> queries or there are   other mechanism that can make the behavior sane?
>

I think it should be enough just to switch to CIM_SINGLE and increment
the command counter after each inserted row.

> Which leaves us with (b) and (c). Clearly, (b) is simpler to implement,
> because it (c) needs to do the detection too, and then some additional
> stuff. I'm not sure how much more complex (c) is, compared to (b).
>
> The attache patch implement option b prohibit VOLATILE functions but i
> am open to change

OK. I'll take a look.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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