Hierarchical Database

What does Hierarchical Database mean?

A hierarchical database is a Data Model that stores data in a hierarchical structure, similar to a tree. Each node in the tree can have multiple child nodes, but only one parent node. The root node is the top of the hierarchy and has no parent.

Hierarchical databases are often used to model real-world relationships. For example, a company’s organizational structure can be represented as a hierarchical database, with the CEO at the root node and employees arranged in a hierarchy beneath them.

Hierarchical databases have a number of advantages over other data models. They are simple to design and implement, and they can efficiently store and retrieve data that is organized in a hierarchical manner. However, hierarchical databases are not well-suited for storing data that does not fit into a hierarchical structure.

Applications

Hierarchical databases are used in a Variety of applications, including:

• Company organizational structures: Hierarchical databases can be used to model the organizational structure of a company, with the CEO at the root node and employees arranged in a hierarchy beneath them. This data model can be used to track employee relationships, manage employee records, and generate organizational charts.
• Product hierarchies: Hierarchical databases can be used to model product hierarchies, with the root node representing the top-level category and child nodes representing subcategories and products. This data model can be used to organize product information, manage inventory, and generate product catalogs.
• Geographic hierarchies: Hierarchical databases can be used to model geographic hierarchies, with the root node representing the world and child nodes representing countries, states, counties, and cities. This data model can be used to store geographic information, such as population data, land use data, and road networks.

Hierarchical databases are particularly well-suited for applications where data is naturally organized in a hierarchical structure. However, they can also be used to store data that does not fit into a hierarchical structure, although this may require some data manipulation.

History

Hierarchical databases were first developed in the 1960s as a way to store data in a structured manner. The first hierarchical database management system (DBMS) was IMS, which was released by IBM in 1966. IMS was followed by a number of other hierarchical DBMSs, including IDS, ADABAS, and VSAM.

Hierarchical databases were widely used in the 1970s and 1980s, but their popularity declined in the 1990s as relational databases became more popular. Relational databases are more flexible than hierarchical databases, and they can store data that does not fit into a hierarchical structure.

However, hierarchical databases are still used in some applications today, especially in applications where data is naturally organized in a hierarchical structure. For example, hierarchical databases are still used to store company organizational structures, product hierarchies, and geographic hierarchies.