postgres-xc-general Mailing List for Postgres-XC

What do you exactly mean by saying that triggers are not supported?

Is it that in the context of single datanode, they will still work,
but the changes are not replicated over the whole XC cluster? Making
the cluster inconsistent?

If the triggers are not supported, how come you passed all the
postgres regression tests?

Thanks






On Thu, Jan 17, 2013 at 12:12 AM, Ashutosh Bapat
<ash...@en...> wrote:
> On Thu, Jan 17, 2013 at 9:26 AM, Filip Rembiałkowski
> <fil...@gm...> wrote:
>> Huh, these are really interesting questions :-)
>>
>> Let me ask them instead as a proof that userbase is interested.
>>
>> 1) Is there support for triggers in Postres-XC? Are there any
>> limitations? Known issues?
>>
>
> Triggers will be supported in next release; we are working on that.
>
>> 2) Does it make sense to run datanodes over distant links (think WAN
>> or intercontinental) ?
>>
>
> No, at least not in next few versions. XC being a scalability
> solution, WAN or intercontinental links do not help; they slow down
> things. As of now, XC is susceptible to network failures/glitches.
> Using WAN or intercontinental links might cause network failures or
> glitches, which will cause XC to behave erratically. We haven't tested
> XC in such environment, so can't describe exact problems it will face.
>
>> Thanks && Regards,
>> Filip Rembiałkowski
>>
>>
>> On Wed, Jan 16, 2013 at 9:15 PM, Michael Paquier <mi...@ot...> wrote:
>>
>>> In order to get answers to your questions, I highly recommend that you
>>> send your messages to the Postgres-XC mailing lists, in your case
>>> pos...@li....
>>
>> ------------------------------------------------------------------------------
>> Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS,
>> MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current
>> with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft
>> MVPs and experts. ON SALE this month only -- learn more at:
>> http://p.sf.net/sfu/learnmore_122712
>> _______________________________________________
>> Postgres-xc-general mailing list
>> Pos...@li...
>> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general
>
>
>
> --
> Best Wishes,
> Ashutosh Bapat
> EntepriseDB Corporation
> The Enterprise Postgres Company

Well, asynchronous replica is not that simple in XC if it is
log-shipping and hot standby.   Hot standby implements different means
to provide consistent MVCC view and we need corresponding means, which
could be a bit complicated than current GTM technique.

Communication between coordinator/datanode via WAN will be a
bottleneck.   Why do you need to install servers in different
locations?   For disaster?    For locality and management?   We should
expect such usecase in the future.   If very few data is shared among
subcluster, I think we can design a feasible architecture.

Regards;
----------
Koichi Suzuki


2013/1/17 Nikhil Sontakke <ni...@st...>:
> Hi Filip,
>
>
>> 1) Is there support for triggers in Postres-XC? Are there any
>> limitations? Known issues?
>>
>
> I believe the support for this feature is being worked upon. But not
> present in the current source base as of now.
>
>> 2) Does it make sense to run datanodes over distant links (think WAN
>> or intercontinental) ?
>>
>
> You can definitely place your datanodes wherever you want them.
> However note that queries will be routed via the coordinator to them
> and results will be brought back from datanodes to the coordinator. So
> distant datanodes might not perform that well here.
>
> What might make more sense would be is to have async replicas (again
> synchronous replicas might not help here) of these datanodes on these
> distant links.
>
> So probably a tighter PGXC cluster with distance datanode async replicas. YMMV
>
> Regards,
> Nikhils
>
>
>> Thanks && Regards,
>> Filip Rembiałkowski
>>
>>
>> On Wed, Jan 16, 2013 at 9:15 PM, Michael Paquier <mi...@ot...> wrote:
>>
>>> In order to get answers to your questions, I highly recommend that you
>>> send your messages to the Postgres-XC mailing lists, in your case
>>> pos...@li....
>>
>> ------------------------------------------------------------------------------
>> Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS,
>> MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current
>> with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft
>> MVPs and experts. ON SALE this month only -- learn more at:
>> http://p.sf.net/sfu/learnmore_122712
>> _______________________________________________
>> Postgres-xc-general mailing list
>> Pos...@li...
>> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general
>
>
>
> --
> StormDB - http://www.stormdb.com
> The Database Cloud
> Postgres-XC Support and Service
>
> ------------------------------------------------------------------------------
> Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS,
> MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current
> with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft
> MVPs and experts. ON SALE this month only -- learn more at:
> http://p.sf.net/sfu/learnmore_122712
> _______________________________________________
> Postgres-xc-general mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general

On Thu, Jan 17, 2013 at 9:26 AM, Filip Rembiałkowski
<fil...@gm...> wrote:
> Huh, these are really interesting questions :-)
>
> Let me ask them instead as a proof that userbase is interested.
>
> 1) Is there support for triggers in Postres-XC? Are there any
> limitations? Known issues?
>

Triggers will be supported in next release; we are working on that.

> 2) Does it make sense to run datanodes over distant links (think WAN
> or intercontinental) ?
>

No, at least not in next few versions. XC being a scalability
solution, WAN or intercontinental links do not help; they slow down
things. As of now, XC is susceptible to network failures/glitches.
Using WAN or intercontinental links might cause network failures or
glitches, which will cause XC to behave erratically. We haven't tested
XC in such environment, so can't describe exact problems it will face.

> Thanks && Regards,
> Filip Rembiałkowski
>
>
> On Wed, Jan 16, 2013 at 9:15 PM, Michael Paquier <mi...@ot...> wrote:
>
>> In order to get answers to your questions, I highly recommend that you
>> send your messages to the Postgres-XC mailing lists, in your case
>> pos...@li....
>
> ------------------------------------------------------------------------------
> Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS,
> MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current
> with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft
> MVPs and experts. ON SALE this month only -- learn more at:
> http://p.sf.net/sfu/learnmore_122712
> _______________________________________________
> Postgres-xc-general mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general



-- 
Best Wishes,
Ashutosh Bapat
EntepriseDB Corporation
The Enterprise Postgres Company

Hi Filip,


> 1) Is there support for triggers in Postres-XC? Are there any
> limitations? Known issues?
>

I believe the support for this feature is being worked upon. But not
present in the current source base as of now.

> 2) Does it make sense to run datanodes over distant links (think WAN
> or intercontinental) ?
>

You can definitely place your datanodes wherever you want them.
However note that queries will be routed via the coordinator to them
and results will be brought back from datanodes to the coordinator. So
distant datanodes might not perform that well here.

What might make more sense would be is to have async replicas (again
synchronous replicas might not help here) of these datanodes on these
distant links.

So probably a tighter PGXC cluster with distance datanode async replicas. YMMV

Regards,
Nikhils


> Thanks && Regards,
> Filip Rembiałkowski
>
>
> On Wed, Jan 16, 2013 at 9:15 PM, Michael Paquier <mi...@ot...> wrote:
>
>> In order to get answers to your questions, I highly recommend that you
>> send your messages to the Postgres-XC mailing lists, in your case
>> pos...@li....
>
> ------------------------------------------------------------------------------
> Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS,
> MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current
> with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft
> MVPs and experts. ON SALE this month only -- learn more at:
> http://p.sf.net/sfu/learnmore_122712
> _______________________________________________
> Postgres-xc-general mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general



-- 
StormDB - http://www.stormdb.com
The Database Cloud
Postgres-XC Support and Service

Huh, these are really interesting questions :-)

Let me ask them instead as a proof that userbase is interested.

1) Is there support for triggers in Postres-XC? Are there any
limitations? Known issues?

2) Does it make sense to run datanodes over distant links (think WAN
or intercontinental) ?

Thanks && Regards,
Filip Rembiałkowski


On Wed, Jan 16, 2013 at 9:15 PM, Michael Paquier <mi...@ot...> wrote:

> In order to get answers to your questions, I highly recommend that you
> send your messages to the Postgres-XC mailing lists, in your case
> pos...@li....