Database Management System (DBMS) / Types of Databases

Network Databases

A Network Database is a type of database that represents data as records connected by multiple relationships, forming a graph-like structure.

Unlike hierarchical databases (which allow only one parent per child), network databases support many-to-many relationships — meaning a child can have multiple parents.

It was designed to overcome the rigidity of hierarchical models by allowing more flexible connections.


🧱 Key Concepts

Concept

Description

Record

A data entity (similar to a row)

Set

A relationship between records

Owner

The parent in a set (relationship)

Member

The child in a set

Many-to-Many

A record can belong to multiple sets


🧠 Key Features

Feature

Description

🔁 Multiple relationships

Supports complex many-to-many connections

⛓️ Set-based access

Data navigated using sets (not tables)

⚡ High performance

Efficient for complex queries and traversals

💾 Schema required

Must define records and sets beforehand


✅ Advantages

Advantage

Description

✅ Flexible relationships

Supports many-to-many natively

✅ Efficient access

Fast retrieval with proper set navigation

✅ Better than hierarchy

Removes single-parent limitation

✅ Good for complex data

Works well for modeling networks, systems, maps


❌ Disadvantages

Disadvantage

Description

❌ Complex structure

Hard to design and maintain

❌ Navigation is manual

Requires navigating through sets, no SQL

❌ Poor flexibility

Schema must be defined early and is hard to change

❌ Low popularity

Largely replaced by RDBMS and NoSQL solutions


🧰 Popular Network DBMS

Database

Description

IDMS (Integrated Database Management System)

Developed by CA Technologies, used in legacy systems

TurboIMAGE

Used in HP systems

Raima Database Manager

Embedded network DB

Univac DMS

Used in older mainframe systems


📍 Use Cases

Use Case

Why Network DB Works

📡 Telecommunication systems

Handle complex routing and dependencies

📚 Library catalog systems

Books, authors, publishers (many-to-many)

🧮 Bill of materials (BoM)

One component used in multiple products

🛠️ CAD/CAM systems

Objects reused in multiple designs


🆚 Network vs Hierarchical vs Relational

Feature

Hierarchical DB

Network DB

Relational DB

Structure

Tree

Graph (sets)

Tables

Relationship Type

1-to-many

Many-to-many

Many-to-many

Flexibility

Low

Medium

High

Query Language

Navigational

Navigational

SQL

Best For

Strict hierarchies

Complex relationships

General-purpose