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.vondra@2ndquadrant.com <mailto:tomas.vondra@2ndquadrant.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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