Stephanie Chatagner's Blog

Well.

Historically, three types of database model groups are observed.

Early Database Model

• Hierarchical model, only one parent, very slow
• Network model, multiple parent

Relational Data Models

• Entity-relationship model
  • based on two concepts:
    • Entities, defined as tables that hold specific information (data)
    • Relationships, defined as the associations or interactions between entities
  • optimized for addition, updating and deletion of data in a real-time Online Transaction System.
  • Between entity, there are relationships and entity have attributes.
• Dimensional model
  • developed by Ralph Kimball and consists of fact and dimension tables.
  • designed to read, summarize, analyze numeric information like values, balances, counts, weights
  • Steps of Dimensional Modelling:
    1. Identify Business Process WHY?
    2. Identify Grain (level of detail) HOW MUCH?
    3. Identify Dimensions 3WS?
    4. Identify Facts WHAT?
    5. Build Start (the schema)

Post-relational Data Models

Here the two ones that I meet most often in my research

• Graph Model
  • Database designed to treat the relationships between data as equally important to the data itself. It is intended to hold data without constricting it to a pre-defined model.
  • Data is stored like we first draw it out - showing how each individual entity connects with or is related to others.
• Object-oriented database models
  • In object-oriented programming, everything is an object, and many objects are quite complex, having different properties and methods. An object-oriented database management system works in concert with an object-oriented programming language to facilitate the storage and retrieval of object-oriented data.

Today, the highlight was to have an overview of the database model.

So, step by step and keep learning!