Arrangement of Entities in Cognos FM model for a Enterprise wide DWH

[avarshney]

Hi,

We have been developing a EDW business layer in Cognos.
The DWH has several datamarts with conformed dimensions between them viz.
>   Sales
>   Finance > General Ledger
                  > Invoice
etc.

We have requirements for Cross Functional Analysis between the datamarts. e.g For a particular Fiscal Period report Sales Quantity as well as Financial Revenue.

I am not sure as to how to model the Warehouse as a Framework Manager Model and need some expert views.

Because crossfunctional analysis is needed, it surely has to be a single package as Cognos does not allow reports coming from two different packages.
Now in a single package:
If I look at the Go Datawarehouse Sample Package, the sample package uses a single metadata layer and another layer on top of it, where they have put shortcuts of entities.
A Business Layer, where we define Business names, Aliases and joins for the entities has to be there. But shortcuts don't seem to be possible in my case as I do not want to show the surrogate keys to the users and if you make shortcuts , the whole table is shown in the package and individual columns can not be excluded. Other way out is - If I choose to have several namespaces each for a Datamart, then I am repeating the conformed dimensions. Here, will I need to define the joins again. Also, in this case I am not sure if the joins shall work fine, for cross functional analyses.

Also, we have to model so that change maintenance is minimum, in the sense, if there is a change in an entity's property in database then we do not have to change the entity's property at multiple places in the model.

Please throw some light on the topic. Are there some best practices discovered for the modelling of EDWs in Framework Manager.

Regards
Anubhuti

[cognosfreelancer]

Hi Anubhuti

Personally I hate to use shortcuts beyond the simplest needs, avoid shortcuts for any complex needs. That would be my recommendation.

Use at least 2 namespaces. I prefer to use three.

Use conforming dimensions and star schema groupings. This will enable your reporting needs to traverse multiple fact subjects.

Attached is a document that I have created outlining what I perceive to be best practices for FM modeling.

I based this on experience and discussions with my peers. This is a living document I welcome the comments of all to make it better.

HTH
NKT

[avarshney]

Thanks NKT, that was experiance documented.

[praveen.h]

Hi NKT,

I want to see the document you have attached, and wanted to use it as a reference(if it is useful to me)...But when I tried to download the file,I am getting an error message "documet not found". Can you please reattach the document so that it will be useful to all who need it.

Thanks in advance.

Praveen.

[avarshney]

Hi NKT,

The document attached is no longer available on the site. Please attach is again.

Best Regards
Anubhuti

[cognosfreelancer]

Wonder what happened

I have re attached the document.

NKT