postgres-xc-developers

Re: [Postgres-xc-developers] Replicated update and delete

[Koichi S. <koi...@gm...>]

Mason;

Thanks for this big patch.    I understand the intention and would like
other members to look at this patch too.

I'd like to know your idea if this can be a part of the TRIGGER improvement?

Regards;

---
Koichi Suzuki


2013/11/2 Mason Sharp <ms...@tr...>

> Please see attached patch that tries to address the issue of XC using CTID
> for replicated updates and deletes when it is evaluated at a coordinator
> instead of being pushed down.
>
> The problem here is that CTID could be referring to a different tuple
> altogether on a different data node, which is what happened for one of our
> Postgres-XC support customers, leading to data issues.
>
> Instead, the patch looks for a primary key or unique index (with the
> primary key preferred) and uses those values instead of CTID.
>
> The patch could be improved further.  Extra parameters are set even if not
> used in the execution of the prepared statement sent down to the data nodes.
>
> Regards,
>
>
> --
> Mason Sharp
>
> TransLattice - http://www.translattice.com
> Distributed and Clustered Database Solutions
>
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Re: [Postgres-xc-developers] Replicated update and delete

[Mason S. <ms...@tr...>]

On Mon, Nov 4, 2013 at 8:17 PM, Koichi Suzuki <koi...@gm...> wrote:

> Mason;
>
> Thanks for this big patch.    I understand the intention and would like
> other members to look at this patch too.
>

Sure.


>
> I'd like to know your idea if this can be a part of the TRIGGER
> improvement?
>

What did you have in mind? Yes, this impacts triggers as well.

Regards,

Mason


>
>
> 2013/11/2 Mason Sharp <ms...@tr...>
>
>> Please see attached patch that tries to address the issue of XC using
>> CTID for replicated updates and deletes when it is evaluated at a
>> coordinator instead of being pushed down.
>>
>> The problem here is that CTID could be referring to a different tuple
>> altogether on a different data node, which is what happened for one of our
>> Postgres-XC support customers, leading to data issues.
>>
>> Instead, the patch looks for a primary key or unique index (with the
>> primary key preferred) and uses those values instead of CTID.
>>
>> The patch could be improved further.  Extra parameters are set even if
>> not used in the execution of the prepared statement sent down to the data
>> nodes.
>>
>>
>>
-- 
Mason Sharp

TransLattice - http://www.translattice.com
Distributed and Clustered Database Solutions