Page 109 - DCAP603_DATAWARE_HOUSING_AND_DATAMINING
P. 109

Unit 5: Data Warehouse Research – Issues and Research




          Fill in blanks:                                                                       notes
          3.   The source systems for a ..................... are typically transaction processing applications.

          4.   The data is extracted completely from the source system known as .....................
          5.   ..................... is based on a comparison of the data loaded into business intelligence and the
               application data in the source system.
          6.   Data  reconciliation  for  DataSources  allows  you  to  check  the  .....................  of  the  loaded
               data.
          7.   The ..................... of the data and the processes of the data warehouse is heavily dependent
               on the design process.
          8.   .....................  is  related  to  the  accessibility  dimension,  since  the  sooner  the  queries  are
               answered.
          9.   .....................  defined  quality  as  the  loss  imparted  to  society  from  the  time  a  product  is
               shipped.
          10.   Three perspective of data warehouse metadata are logical, physical and .....................

          5.12 review Questions

          1.   What do you mean by data extraction?

          2.   Describe logical extraction methods of data.
          3.   Distinguish between online and offline extraction.
          4.   Explain modeling aspects of data reconciliation.
          5.   What do you mean by data aggregation?

          6.   Describe basic principles of query optimization.
          7.   Explain various strategies of query optimization.
          8.   “As a decision support information system, a data warehouse must provide high level
               quality of data and quality of service”. Explain

          9.   Write a short note on data quality research.
          10.   What are the three perspectives of data warehouse metadata?

          answers: self assessment

          1.   (a)                               2.   (c)
          3.   data warehouse                    4.   Full extraction
          5.   Data reconciliation               6.   integrity
          7.   interpretability                  8.   Query optimization

          9.   Taguchi                           10.  Conceptual













                                           LoveLy professionaL university                                   103
   104   105   106   107   108   109   110   111   112   113   114