Data models are conceptual representations of how data is organized and structured. They provide a blueprint for storing, managing, and retrieving data in a database or data storage system. There are several types of data models, each with its strengths and weaknesses. Here are some common data models with examples:
A relational data model organizes data into tables with well-defined relationships between them. Each table has rows and columns, where each row represents a single record and each column represents a field or attribute of that record.
Students Table
| StudentID (Primary Key) | Name | Age | DepartmentID (Foreign Key) |
|---|---|---|---|
| 1 | John Doe | 20 | 1 |
| 2 | Jane Smith | 22 | 2 |
| 3 | Bob Johnson | 21 | 1 |
Courses Table
| CourseID (Primary Key) | CourseName | DepartmentID (Foreign Key) |
|---|---|---|
| 1 | Math 101 | 1 |
| 2 | Science 202 | 2 |
| 3 | History 303 | 1 |
A hierarchical data model organizes data into a tree-like structure, with each node representing a record or a group of records.
Company
graph TD
Company --> Department1
Company --> Department2
Department1 --> Employee1
Department1 --> Employee2
Department2 --> Employee3
Department2 --> Employee4
A network data model organizes data into a graph structure, with each node representing a record or a group of records, and edges representing relationships between them.
An Entity Relationship (ER) Diagram is a type of flowchart that illustrates how “entities” such as people, objects or concepts relate to each other within a system.
Refer to:
Diagram: Link
