Database Management System Emulation - Information Systems Reengineering, Integration and Normalization - page 229

Phase II (step 2.1)

Nonrelational
schema +
secondary

nonrelational
schema

Schema Restructure

Phase I

Phase II (step 2.2)

Schema translation

nonrelational
Database

Schema Restructure

Embedded-
SQL
programs

translated
relational
schema

nonreational
database +
secondary
indices

Phase II (step2.3) Phase II (step2.4)

Program translation nonrelational DBMS

processing

Phase III

Translated
nonrelational
programs

Converted
relational
database

Data conversion

Fig. 6.1 Methodology “RELIKEDB” data flow diagram

6.2 Case Study of Converting a Hierarchical Database

to Relational

The case used is a patient information system for a group of public hospitals. The his-
tory of the patient's stay in the hospital is stored including the ward, their symptoms,
and treatments. The facilities of the hospital are also stored. The hierarchical schema of
the patient information system and source hierarchical database is shown in Fig. 6.2 :
The source hierarchical database for the patient information system is:

Segment HOSPITAL

HOSPNAME HOSPHONE ADMINTOR

MAC NEAL 123-7890 SHU MAKE

RIVEREDGE 654-3210 PAY N E

Segment WARD

WARDNO TOTROOMS TOTBEDS BEDAVAIL WARDTYPE

01 20 30 018 CARDIOVASC