In IMS DB (Information Management System Database), data is organized hierarchically. This hierarchical organization is a fundamental aspect of IMS DB and shapes how data is stored, accessed, and managed within the database. Here's how data is organized in IMS DB:

Root Segment : At the top level of the hierarchy is the root segment. The root segment serves as the starting point for accessing data within the database. It typically represents the highest-level entity or concept being modeled, such as a customer, product, or account.

Parent-Child Relationships : Data in IMS DB is organized into parent-child relationships. Each segment in the database can have one or more child segments associated with it, forming a hierarchical structure. This hierarchical arrangement allows for the representation of complex relationships between data elements.

Segments : Segments are the basic building blocks of data organization in IMS DB. Each segment represents a logical grouping of related data elements or fields. Segments are interconnected through parent-child relationships, with parent segments containing child segments. This hierarchical structure enables efficient data retrieval and manipulation.
Occurrence Number : Segments can have multiple occurrences, allowing for the storage of repeating data structures. The occurrence number identifies each instance or occurrence of a segment within the database. This feature enables IMS DB to handle data with varying cardinalities and repeating patterns.

Hierarchical Access Paths : IMS DB provides hierarchical access paths for navigating the database hierarchy and accessing specific segments or records. These access paths define the sequence of segments to be traversed to reach a desired segment within the hierarchy. By following these paths, applications can efficiently retrieve and manipulate data within the database.