Adatmodellezést

Adatmodellezést, or data modeling, is the process of creating a visual representation of an information system. It's a fundamental step in database design and software development, helping to define the structure, relationships, and constraints of data. Data modeling typically involves three levels: conceptual, logical, and physical.

The conceptual model is the highest level of abstraction, focusing on business concepts and rules. It's typically created with input from stakeholders to understand the business requirements. The logical model translates the conceptual model into a more detailed representation, often using entities, attributes, and relationships. This model is independent of any specific database technology. The physical model is the most detailed level, specifying how the data will be stored in a particular database system, including data types, indexes, and table structures.

Data modeling serves several important purposes. It aids in understanding complex data requirements, facilitates communication between developers and business users, and forms the blueprint for database implementation. Well-designed data models lead to more efficient, consistent, and maintainable databases. They help to identify potential data redundancy, ensure data integrity, and optimize query performance. Various notations and methodologies exist for data modeling, such as Entity-Relationship Diagrams (ERD) and Unified Modeling Language (UML).