Long running queries   

We're considering using xmla to expose our cube data, but I have a
concern.  Queries against our large ROLAP databases could take many
minutes to return.  Should we be worried about holding an HTTP
connection open for that long?   It seems that if multiple users are
all opening long running queries the resource demand on IIS could be
excessive.

date: 16 Feb 2006 14:21:02 -0800   author:   unknown

Re: Long running queries   

If your load is very heavy with lots of active concurrent users then yes, 
this could be a problem. You can scale your IIS server out to multiple 
virtual directories/servers to reduce the impact.

Thanks,
Akshai

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 wrote in message 
news:1140128462.091926.169660@g43g2000cwa.googlegroups.com...
>
> We're considering using xmla to expose our cube data, but I have a
> concern.  Queries against our large ROLAP databases could take many
> minutes to return.  Should we be worried about holding an HTTP
> connection open for that long?   It seems that if multiple users are
> all opening long running queries the resource demand on IIS could be
> excessive.
>

date: Fri, 17 Feb 2006 11:32:34 -0800   author:   Akshai Mirchandani [MS]

Re: Long running queries   

Thanks for the reply, Akshai.  I think balancing out the load across
multiple servers is certainly something we'd have to do.  I am
concerned, however, that no matter how many instances of IIS we are
hosting there may be a problem.  If a query takes a very long time--say
2 hours--can we really be confident that the HTTP connection won't be
broken?  My sense is that HTTP is not typically geared toward requests
that last that long.

Another question--we are currently running AS 2000.  My understanding
is that with AS 2005 the only way to connect is using xmla, is that
correct?

date: 21 Feb 2006 11:03:19 -0800   author:   unknown

Re: Long running queries   

One more question--is it possible to use a non-HTTP binding to xmla?

date: 21 Feb 2006 11:08:58 -0800   author:   unknown

Re: Long running queries   

HTTP can handle long-running requests -- you may need to adjust timeouts in 
IIS but it should work. 2 hours is a little extreme though :) I would 
consider other solutions for this -- e.g. your own web service that in the 
background executes the query over XMLA, saves the result and then returns 
it on demand -- or something like that. This way you could build your own 
custom handling of users and XMLA virtual directories, etc.

AS 2005 uses the XMLA protocol. But it has two transports -- HTTP and TCP. 
The TCP transport is however not publicly documented.

As far as your next question: the XMLA SDK only supports the HTTP binding --  
theoretically other bindings could also be used, but the XMLA spec does not 
discuss/document/support them.

Thanks,
Akshai
--
This posting is provided "AS IS" with no warranties, and confers no rights
Please do not send email directly to this alias. This alias is for newsgroup
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 wrote in message 
news:1140548599.150623.103640@o13g2000cwo.googlegroups.com...
> Thanks for the reply, Akshai.  I think balancing out the load across
> multiple servers is certainly something we'd have to do.  I am
> concerned, however, that no matter how many instances of IIS we are
> hosting there may be a problem.  If a query takes a very long time--say
> 2 hours--can we really be confident that the HTTP connection won't be
> broken?  My sense is that HTTP is not typically geared toward requests
> that last that long.
>
> Another question--we are currently running AS 2000.  My understanding
> is that with AS 2005 the only way to connect is using xmla, is that
> correct?
>

date: Tue, 21 Feb 2006 12:19:32 -0800   author:   Akshai Mirchandani [MS]