Data Analytics - Data Modelling
Data modelling is a crucial step in the process of organizing and structuring data to represent the relationships and constraints within a database or information system. It provides a blueprint for designing databases that accurately reflect the real-world entities and their interactions.
Here’s a guide of the steps that we perform in data modelling for our customers:
- Identify Business Requirements: Understand the business requirements and objectives that the database or system should address. Gather information about data sources, entities, relationships, and user needs.
- Conceptual Data modelling: Create a high-level conceptual data model that represents the overall structure and relationships of the data without focusing on technical implementation. This model is often represented using Entity-Relationship (ER) diagrams.
- Identify Entities and Attributes: Identify the key entities within the domain. For each entity, determine its attributes (properties) that hold relevant information.
- Define Relationships: Define the relationships between entities. Specify whether the relationships are one-to-one, one-to-many, or many-to-many. Relationships add context and meaning to the data.
- Normalize or De-Normalize Data: Apply normalization/ De-normalization techniques to ensure that the data is organized efficiently and without redundancy. Normalize the data to eliminate data anomalies and improve data integrity. De-Normalize the data to achieve faster data retrieval for Reporting needs.
- Logical Data modelling: Translate the conceptual model into a logical data model that is more detailed and defines the structure of the database, including tables, columns, primary keys, and foreign keys. Use tools like Entity-Relationship diagrams or Unified modelling Language (UML) class diagrams.
- Physical Data modelling: Convert the logical data model into a physical data model in the form of Tables and Views that's optimized for a specific database management system (DBMS).
- Documentation: Document the entire data modelling process, including the conceptual, logical, and physical models, constraints, relationships, and any design decisions made.
- Validation and Review: Review the data model with stakeholders, including domain experts, developers, and users. Validate that the model accurately represents the business requirements.
- Iterate and Refine: Based on feedback and validation results, make necessary revisions to the data model. Data modelling is often an iterative process, refining the model until it accurately represents the domain.
- Implementation and Integration: Work closely with database developers to implement the data model in the chosen DBMS. Ensure that the physical implementation matches the logical design.
- Testing and Validation: Test the implemented database for functionality, data integrity, and performance. Validate that the database meets the defined business requirements.
- Maintenance and Evolution: As the business evolves, we adapt and modify the data model. Regularly review and update the data model to accommodate changes in the business environment.