Information Systems Reengineering, Integration and Normalization - Information Systems Reengineering, Integration and Normalization - page 28

tion must be done after schema integration and schema translation. An ES can be
reused by integrating it with a new or existing database system. The resultant EDS
is the core information resource system for a company for future reengineering pur-
poses. The problems in database reengineering are in the handling of different data
structures of various data models. Also the existing ESs can become obsolete due to
changes of user requirements and production databases. The suggested solution is
to upgrade record-based data models of hierarchical or network databases to table
oriented relational databases, object-oriented databases, and XML databases. We
can also reuse ESs by integrating them with the database into an EDS. An example
of the application of reengineering can be seen in the electronic data interchange on
the Internet. The EDI system can help trading companies exchange information for
their business. However, EDI needs programming solutions that are too expensive
and not promptly developed. The alternative is to use XMLRT and XML document
as a medium for data transmission on the Internet. Since XML is the default data
standard on the Internet, which can be browsed through Internet Explorer without
programming, the XMLRT and XML document solution can perform better with
less cost than EDI. We will show how to perform data transformation between rela-
tional data and an XML document in the later chapters.
Questions
Question 1.1
What is an expert system, an expert database system and a knowledge-based
system? What are their major differences?
Question 1.2
How can one validate and measure the quality of a converted database?
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