postgres-xc-developers Mailing List for Postgres-XC

On Fri, May 24, 2013 at 1:30 AM, Ashutosh Bapat <
ash...@en...> wrote:

> Hi All,
> While I hear Robert's presentation on query planning go wrong, I heard
> (first time) about MergeAppend plan. It looks like, we have something
> better to do with the way we are pushing the ORDER BY clauses and doing
> merge at the coordinator. Right now we are using Sort node and in ExecSort
> we start merging the rows. Instead, I think we should be using MergeAppend
> node.
>
>
I generally like this idea (though I saw below you did not get performance
numbers as expected). If we do this, it would also make sense to rework
RemoteQuery to use Append nodes for combining unsorted results from the
datanodes. But we will need some kind of parallelism at that node level so
that queries can be started and executed on all the child nodes at the same
time. AFAIK the current Append node executes serially i.e. it will move to
the next node only after finishing one subplan.

Thanks,
Pavan

-- 
Pavan Deolasee
http://www.linkedin.com/in/pavandeolasee

On Thu, Aug 8, 2013 at 9:41 PM, Abbas Butt <abb...@en...> wrote:
> Hi,
> PFA patch to fix an XC limitation that update of a replicated table
> created with oids cannot be based on oids.

When did you change distribution rule to REPLICATION from ROUNDROBIN?
I lost your patch.

> i.e. this update supposed to fail
> update rep_table_with_oids set colum = $1 where oid=$2
> saying
> ERROR : Write to replicated table returned different results from the Datanodes
>
> The reason is that we would select oid from the primary datanode and
> that particular oid will not be there on the rest of the datanodes.
> The patch comments explain the complete scenario in detail.
>
> With this patch the JDBC regression runs without any failures or
> errors on my machine.
> Strangely I did not have to change any thing on the server side.

What do you experience the strangeness of?
Your patch eliminated "oid" column from the selection, therefore,
UPDATE query does not contain "oid" anymore. I think it is
straightforward.

Regards.

>
> --
> Abbas
> Architect
>
> Ph: 92.334.5100153
> Skype ID: gabbasb
> www.enterprisedb.com
>
> Follow us on Twitter
> @EnterpriseDB
>
> Visit EnterpriseDB for tutorials, webinars, whitepapers and more
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Postgres-xc-developers mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>

I hesitated to accept.

Because original testCopyOutByRow tests COPY from a table but our one
tests COPY from a subquery. But I found that it tests to issue COPY
query and to receive the result. The target of COPY is not important.

Hence, I think this patch is applicable.

On Thu, Aug 8, 2013 at 8:06 PM, Abbas Butt <abb...@en...> wrote:
> Hi,
> PFA patch to fix copy tests needing order by.
>
> --
> Abbas
> Architect
>
> Ph: 92.334.5100153
> Skype ID: gabbasb
> www.enterprisedb.com
>
> Follow us on Twitter
> @EnterpriseDB
>
> Visit EnterpriseDB for tutorials, webinars, whitepapers and more
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Postgres-xc-developers mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>

I think "order by" in runInfinityTests is unnecessary.

On Thu, Aug 8, 2013 at 6:33 PM, Abbas Butt <abb...@en...> wrote:
> Hi,
> PFA path to fix time-stamp tests needing order by
>
> --
> Abbas
> Architect
>
> Ph: 92.334.5100153
> Skype ID: gabbasb
> www.enterprisedb.com
>
> Follow us on Twitter
> @EnterpriseDB
>
> Visit EnterpriseDB for tutorials, webinars, whitepapers and more
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Postgres-xc-developers mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>

My comment is same as the one for 10_1_date. patch.

On Thu, Aug 8, 2013 at 6:32 PM, Abbas Butt <abb...@en...> wrote:
> Hi,
> PFA patch to fix time tests needing order by.
>
> --
> Abbas
> Architect
>
> Ph: 92.334.5100153
> Skype ID: gabbasb
> www.enterprisedb.com
>
> Follow us on Twitter
> @EnterpriseDB
>
> Visit EnterpriseDB for tutorials, webinars, whitepapers and more
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Postgres-xc-developers mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>

It will work. But it took a bit time to understand that
selectSQL("testdate order by i", "dt")) is expanded to "SELECT dt FROM
testdate order by i" because the first argument name of selectSQL is
"table".
You'd better use selectSQL (String table, String columns, String
where, String other) rather than selectSQL(String table, String
columns).

On Thu, Aug 8, 2013 at 6:31 PM, Abbas Butt <abb...@en...> wrote:
> Hi,
> PFA patch to fix date tests needing order by.
>
> --
> Abbas
> Architect
>
> Ph: 92.334.5100153
> Skype ID: gabbasb
> www.enterprisedb.com
>
> Follow us on Twitter
> @EnterpriseDB
>
> Visit EnterpriseDB for tutorials, webinars, whitepapers and more
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Postgres-xc-developers mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>

No problem.

On Thu, Aug 8, 2013 at 6:31 PM, Abbas Butt <abb...@en...> wrote:
> Hi,
> PFA patch to fix integer tests needing order by.
>
> --
> Abbas
> Architect
>
> Ph: 92.334.5100153
> Skype ID: gabbasb
> www.enterprisedb.com
>
> Follow us on Twitter
> @EnterpriseDB
>
> Visit EnterpriseDB for tutorials, webinars, whitepapers and more
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Postgres-xc-developers mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers
>