Network Data Model | Advantage | Disadvantage

The network data model extends the hierarchical model by allowing records to have multiple parent and child relationships. It introduces the concept of sets, which represent collections of records. The relationships between records are defined through pointers or links. While this model offers more flexibility than the hierarchical model, it can be challenging to navigate and maintain due to its complex structure. The CODASYL (Conference on Data Systems Language) database management system is an example of a network data model.

Advantages of Network Data Model:

1. Flexibility in Relationships: The network data model allows for many-to-many relationships between data elements. Unlike the hierarchical model, where a record can have only one parent, the network model permits a record to have multiple parent and child connections. This flexibility enables the representation of complex relationships more effectively.
2. Efficient Data Access: Retrieving data in the network model can be efficient, especially when accessing data through direct pointers or links. It allows for direct navigation between connected records, resulting in faster data retrieval compared to hierarchical models.
3. Data Integrity: The network model maintains data integrity by enforcing referential integrity rules. Relationships between records are defined explicitly through pointers, ensuring data consistency and preventing orphan records.
4. Schema Evolution: The network model supports schema evolution, meaning that it can adapt and evolve as new relationships or data elements are introduced. It allows for modifications to the database schema without requiring significant changes to the existing data.

Disadvantages of Network Data Model:

1. Complexity: The network data model can become complex and challenging to understand and maintain, especially as the number of records and relationships grows. Navigating the network structure and comprehending the interconnections between records may require advanced knowledge and expertise.
2. Lack of Standardization: Unlike the hierarchical and relational models, which have well-defined standards and widely adopted query languages, the network model lacks standardization. This lack of standardization can make it challenging to share or integrate data with systems that use different data models.
3. Scalability and Performance: As the network model expands with the addition of more records and relationships, it can become less scalable and performance-intensive. Traversing complex networks and executing complex queries across multiple connections can result in slower performance and increased resource consumption.
4. Maintenance Overhead: Maintaining the network model can be labor-intensive and time-consuming. Adding, deleting, or modifying relationships may require extensive modifications to the database structure and can lead to a higher maintenance overhead.

Conclusion:

The network data model offers greater flexibility and more expressive power in representing complex relationships compared to the hierarchical model. It allows for efficient data access through direct pointers and maintains data integrity. However, the network model’s complexity, lack of standardization, scalability challenges, and maintenance overhead make it less favored in modern database systems. The emergence of the relational model and the subsequent evolution of NoSQL databases have addressed many of these disadvantages and provided more scalable, standardized, and flexible alternatives for managing complex data structures.