Network Data Models
A network data model is a type of database model that represents data as a collection of nodes and edges.
In this model, data is organized as interconnected nodes, where each node represents an entity (such as a person, place, or thing), and each edge represents a relationship between nodes.
Nodes & Edges
Nodes
Nodes are the fundamental units of data in the network model. Each node typically contains attributes or properties that describe the entity it represents.
Edges
Edges, also known as arcs or links, represent relationships between nodes. These relationships can be one-to-one, one-to-many, or many-to-many.
Structure of Network Data Models
Unlike the hierarchical model where each record has a single parent, the network model allows a node to have multiple parent nodes.
This feature enables the representation of complex relationships more accurately.
Record Types
Nodes in a network model can belong to different record types, each with its own set of attributes and relationships.
This flexibility allows for modeling diverse types of entities and relationships within the same database.
Navigational Access
Retrieving data in a network database often involves navigating through the interconnected nodes using pointers or links.
This navigational access method contrasts with the more structured query languages used in relational databases.
Advantages of Network Data Models
Flexibility in Relationships
Supports many-to-many relationships, ideal for modeling interconnected data.
Efficient Querying
Navigational access enables efficient retrieval by following links between nodes.
Data Integrity
Provides mechanisms for maintaining data integrity, ensuring consistency.
Schema Flexibility
Allows for schema modifications without extensive alterations.
Disadvantages
Complexity
Design and implementation can be complex, especially for large datasets.
Lack of Standardization
No widely adopted standard query language, making interoperability challenging.
Scalability
May face performance issues with very large datasets or highly dynamic environments.
Limited Support
Less commonly used and supported compared to relational databases.