Re: Parallel Seq Scan

On 10-03-2015 PM 01:09, Amit Kapila wrote:
> On Tue, Mar 10, 2015 at 6:50 AM, Haribabu Kommi <kommi.haribabu@gmail.com>
>> Is this patch handles the cases where the re-scan starts without
>> finishing the earlier scan?
>>
> 
> Do you mean to say cases like ANTI, SEMI Join (in nodeNestLoop.c)
> where we scan the next outer tuple and rescan inner table without
> completing the previous scan of inner table?
> 
> I have currently modelled it based on existing rescan for seqscan
> (ExecReScanSeqScan()) which means it will begin the scan again.
> Basically if the workers are already started/initialized by previous
> scan, then re-initialize them (refer function ExecReScanFunnel() in
> patch).
> 

From Robert's description[1], it looked like the NestLoop with Funnel would
have Funnel as either outer plan or topmost plan node or NOT a parameterised
plan. In that case, would this case arise or am I missing something?

Thanks,
Amit

[1]
http://www.postgresql.org/message-id/CA+TgmobM7X6jgre442638b+33h1EWa=vcZqnsvzEdX057ZHVuw@mail.gmail.com