Page 252 - DCAP603_DATAWARE_HOUSING_AND_DATAMINING

Data Warehousing and Data Mining

notes Although business executives recognize the importance of having highquality data, they discover
that numerous organizational and technical issues make it difficult to reach this objective.
For example, data ownership issues arise from the lack of policies defining responsibility and
accountability in managing data. Inconsistent data-quality requirements of various standalone
applications create an additional set of problems as organizations try to combine individual
applications into integrated enterprise systems. Interorganizational information systems add
a new level of complexity to managing data quality. Companies must resolve the issues of
administrative authority to ensure that each partner complies with the data-quality standards.
The tendency to delegate data-quality responsibilities to the technical teams, as opposed to
business users, is another common pitfall that stands in the way of high-quality data.
Different categories of data quality are proposed by Brauer (2001). They are: standardization (for
consistency), matching (of data if stored in different places), verification (against the source),
and enhancement (adding of data to increase its usefulness). Whichever system is used, once the
major variables and relationships in each category are identified, an attempt can be made to find
out how to better manage the data.
An area of increasing importance is the quality of data that are processed very fast in real time.
Many decisions are being made today in such an environment.

13.1.1 Data Warehouse structure

The Data Warehouse has two main parts:
1. Physical store: A Microsoft SQL Server database that you can query using SQL queries,
and an OLAP database that you can use to run reports.
2. Logical schema: A conceptual model that maps to the data in the physical store.
In figure below shows the relationship between the physical store and the logical schema.

Physical Store

The physical store for the Data Warehouse includes one database that you can query using SQL
queries. The physical store contains all the data that you have imported from different sources.
Commerce Server automatically builds the physical store for the Data Warehouse in both the SQL
Server database and in the OLAP database. The Data Warehouse provides the data necessary for
all the Commerce Server reports available in the Analysis modules in Business Desk.

246 LoveLy professionaL university