Re: dimension vs level

From: Sean Boon [MS] (seanboon_at_online.microsoft.com)
Date: 03/26/04 

Date: Fri, 26 Mar 2004 10:58:37 -0800

Hi Ali,

Transaction numbers are typically not modeled as dimensions or levels in
OLAP cubes. Yes, as you indicate below, Analysis Services loads all
dimension members into memory when the service starts up.

The first thing I'd do is to determine if the requirement from the end users
is to be able to drill into transaction level detail data. If that is the
case, there are multiple ways you can achieve this outside from building a
dimension. You could use drillthrough, or you could build an action which
queries the underlying source tables. You might also want to consider using
Reporting Services and building an AS action that simply makes a call to a
Reporting Services report which would then show the detail level data.
There are lots of options here.

Now, if you're only talking about thousands of transactions, then you could
conceivably model it as a level. If you have 2 or 3GB of memory available
on the machine, you can literally have a few million dimension members
before you need to start considering something like 64-bit.

However, transaction is usually not modeled as a dimension. 

-- 
Sean
-- 
Sean Boon
SQL Server BI Product Unit
-- 
This posting is provided "AS IS" with no warranties, and confers no rights.
Use of included script samples are subject to the terms specified at
http://www.microsoft.com/info/cpyright.htm.
"Ali [Xavor]" <alishahzad***@hotmail.com> wrote in message
news:uFGoZ$0EEHA.4016@TK2MSFTNGP09.phx.gbl...
> Am new to OLAP, designing an analysis db these days. I've a basic question
> regarding dimensions/ level. I have three entities:
> -StoreNo
> --RegisterNo
> ---TransNo
>
> Now transaction numbers repeat across different registers. So I can either
> make it a level of my dimension (trans info) or a separate dimension. What
I
> need to know, is that when the MS AS starts, does it load all disticnt
> members of a level or all rows of a dimension table? Decision is important
> since if it loads all the rows, then it can have significatly load the
> memory- TransNo will have thousands of members and they can form many
> conbimations with store no and reg no
>
> Ali
>
>