How to handle denormalization in B.I data model

How to handle denormalization in B.I data model


As far as I know, normalization is done to avoid inconsistency in the database.

By normalizing we:

  • reduce data redundancy, and
  • protect data integrity.

That's why most OLTP databases are in 3NF.

Different databases from OLTP come together in a data warehouse. (DWH, OLAP). DWHs are denormalized (1FN), and is obvious it has to be like that, because the main table of a DWH has hundreds of columns.

From that DWH we can build several data marts that we would later use for doing analysis with a BI reporting tool (Cognos, QlikView, BO .. )

The problem is that the data model for the BI report is not normalized.

Couldn't that be a problem for redundancy and data integrity for the report?

Hi Saanvi,

I'm not sure what your question is. In general, you wouldn't want your denormalized data in OutSystems, or for that matter in a relational database at all. E.g. in Qlikview you'd read all the data into its local data warehouse-like data store from where all reports are generated.