How Data is Stored in Hierarchical Database?

Answer: In a hierarchical database, data is organised in a tree with a root record, parent-child relationships, and efficient access via unique keys.

1. Root Record: A hierarchical database starts with a single root record, serving as the top-level entity in the hierarchy.
2. Segments or Fields: Each record is divided into segments or fields, representing specific attributes or data elements.
3. Parent-Child Relationships: Records are organised based on parent-child relationships, where each record has a single parent and potentially multiple children.
4. Tree Structure: The data is structured as a tree with the root at the top and subsequent levels forming branches, mirroring a natural hierarchy.
5. Record Identification: Every record is identified by a unique key, and relationships are maintained through pointers or links between parent and child records.
6. Traversal: Accessing data involves traversing the tree structure, starting from the root and navigating down to specific records based on the desired path.
7. Efficiency for Certain Queries: Hierarchical databases are efficient for queries that involve navigating through parent-child relationships, making them suitable for scenarios where a top-down approach is applicable.

Example

IMS (Information Management System) is an example of a hierarchical database, commonly used for managing hierarchical data structures in applications like banking and telecommunications