Database Modeling


Data Modelling : - How data to be stored in a Database, A Data Model is used to document, define, organize, and show how the data structures within a given database, architecture, application, or platform are connected, stored, accessed, and processed within the given system and between other systems.

Its conceptual representation of
  • Data objects
  • The associations between different data objects
  • The rules.
Data model emphasizes on what data is needed and how it should be organized instead of what operations need to be performed on the data. Data Model is like architect's building plan which helps to build a conceptual model and set the relationship between data items
 The two types of Data Models techniques are
  1. Entity Relationship (E-R) Model
  2. UML (Unified Modelling Language)
Types of Data Models : There are mainly three different types of data models:
  1. Conceptual: This Data Model defines WHAT the system contains. This model is typically created by Business stakeholders and Data Architects. The purpose is to organize, scope and define business concepts and rules.
  2. Logical: Defines HOW the system should be implemented regardless of the DBMS. This model is typically created by Data Architects and Business Analysts. The purpose is to developed technical map of rules and data structures.
  3. Physical: This Data Model describes HOW the system will be implemented using a specific DBMS system. This model is typically created by DBA and developers. The purpose is actual implementation of the database.

The 3 basic tenants of Data Model are:
·         Entity: A real-world thing
·         Attribute: Characteristics or properties of an entity
·         Relationship: Dependency or association between two entities 



Types of database models

There are many kinds of data models. Some of the most common ones include:
  • Hierarchical database model
  • Relational model
  • Network model
  • Object-oriented database model
  • Entity-relationship model
  • Document model
  • Entity-attribute-value model
  • Star schema
  • The object-relational model, which combines the two that make up its name

https://medium.com/@stallonejacob/data-modeling-for-business-requirements-98d6538222a0
https://www.lucidchart.com/pages/database-diagram/database-models






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