Re: Datawarehouse->(ETL)->Datamart; Where should ETL be physically located?

From: Geoff Muldoon <>
Date: Mon, 22 Mar 2010 09:20:47 +1100
Message-ID: <>>, guser78 says...

> > > Assume that the 'Data warehouse' and 'Data mart' run on separate
> > > physical servers. In such a case, where does the ETL layer (which is
> > > used to load onto Datamart from Datawarehouse) fit better? Should it
> > > be part of 'Data warehouse' box, or the 'Datamart' box? Why?
> >
> > "Should it be part of 'Data warehouse' box, or the 'Datamart' box?"
> >
> > Neither of them. It should be on a separate ETL server with the ETL
> > tools and processes installed on it (and a lot of free HD space too).
> I agree with that. But, what do you do when you have the option of
> having only 2 physical servers (1->DWH, 1->Datamart, ETL:where?)?

Given that restriction, I'd usually go "on the target rather than the source", because some of my ETL processes are designed so that the transform and load components should only occur if a full extract is successfully completed, and it's easier to deal with network outages in these instances if ETL is on the target.

GM Received on Sun Mar 21 2010 - 17:20:47 CDT

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