Question

Derived data layer in data warehouse .

Answer 1

Each of the three layers has a metadata layer linked with it. The metadata layer describes the properties or characteristics of the data. The operational metadata describe the data used in the various operational and external systems. The enterprise data warehouse metadata describe the reconciled data layer. The data mart metadata describes the derived data layer.

Metadata describe other data. There are three types of metadata used in the three-layer architecture:
1. Operational — describes the data in the operational systems that feed the enterprise data warehouse. May exist in different formats and is often poor quality.
2. Enterprise data warehouse — describes the reconciled data layer as well as the rules for extracting, transforming and loading operational data into reconciled data.
3. Data mart — describes the derived data layer and the rules for transforming reconciled data to derived data

Answer 2

Answer:

The enterprise data warehouse metadata describe the reconciled data layer. The data mart metadata describes the derived data layer. ... Enterprise data warehouse — describes the reconciled data layer as well as the rules for extracting, transforming and loading operational data into reconciled data.