Information Systems Reengineering, Integration and Normalization - Information Systems Reengineering, Integration and Normalization - page 16

Global
database

Relational
Database 1

Step 3. Data Integration

Look Up
Table

:
:

Relational
Database n

Integrated
schema

Step 2. Schema Integration

............

EER Model
1

EER Model
n

Step 1. Reverse Engineering

(for SchemaTranslation)

............

Relational
schema 1

Relational
Schema n

Fig. 1.5 Architecture of multiple databases integration

databases and there is no loss of information after integration. Figure 1.5 shows the
data flow of data integration after schema integration of source relational schemas.

1.3.4 Integration of Database and ESs

Integration of existing databases with a new updated computing technology is
another issue of database reengineering. The integration will update the existing
systems to meet a new requirement. Our main theme, in this section, is to describe
the problem of integrating ES with DBS, i.e., EDS.
The short-term and probably most straightforward strategy for developing an
EDS is to extend existing systems. This approach treats DBSs and/or ESs as starting
points and moves in an evolutionary fashion toward the goal of a knowledge-based
management system. An example of this is enhancing existing relational databases
to include ES technology (an enhanced DBS), or adding an efficient use of second-
ary storage to an existing ES (an enhanced ES).
However, some people believe that allowing a DBS and ES to communicate