Management Information Systems, 13TH ED.
MANAGING THE DIGITAL FIRM
Kenneth C. Laudon ● Jane P. Laudon
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Learning Track 3: Hierarchical and Network Data Models
You can still find older systems that are based on a hierarchical or network data model. e hier–
archical DBMS is used to model one-to-many relationships, presenting data to users in a treelike
structure. Within each record, data elements are organized into pieces of records called segments.
To the user, each record looks like an organizational chart with one top-level segment called the
FIGURE 1 A Hierarchical Database for a Human Resources System.
Chapter 6: Foundations of Business Intelligence: Databases and
Information Management
Chapter 6 Learning Track 3 2
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Compensation connects to Performance Ratings and Salary History. Benefits connects to Pension, Life
Insurance, and Health. Each subordinate segment is the child of the segment directly above it.
Whereas hierarchical structures depict one-to-many relationships, network DBMS depict data
logically as many-to-many relationships. In other words, parents can have multiple children, and
FIGURE 2 The Network Data Model
This illustration of a network data model showing the relationship the students in a university have to the
courses they take represents an example of logical many-to-many relationships.
Hierarchical and network DBMS are considered outdated and are no longer used for building new
database applications. ey are much less exible than relational DBMS and do not support ad
Relational DBMS, in contrast, have much more exibility in providing data for ad hoc queries,
combining information from dierent sources, and providing capability to add new data and
records without disturbing existing programs and applications. However, these systems can be
Chapter 6 Learning Track 3 3