— blog
Database
Let's explore the source of my reflections — on data, AI, and everything that sits between a raw dataset and a good decision — turn complexity into clarity, and share it all in the most naive way.
- Jul 24 min
Dimensional Modeling - Part 3: Dimensions Hierarchy
Data WarehouseDatabaseData EngineeringData ModelingThis article examines various hierarchy types in data modeling, including Fixed Depth Positional Hierarchies, Slightly Ragged Hierarchies, and Ragged Hierarchies. Fixed Depth Hierarchies feature clear many-to-one relationships, such as product to brand, allowing for easy navigation and quick queries. The article discusses strategies for managing ragged hierarchies through the use of bridge tables and pathstring attributes to simplify analysis and improve performance.
- Jul 16 min
Data Modeling
Data WarehouseDatabaseData ModelingData EngineeringThis article explores the importance of Data Modeling as a foundational blueprint for organizing information within a business, aiding in the development of a data warehouse. It emphasizes the role of a Logical Data Model (LDM) in establishing frameworks for business intelligence and analytics, ensuring data consistency, quality, and effective communication. The article also contrasts Online Transactional Processing (OLTP) and Online Analytical Processing (OLAP) models and summarizes the transition from a Logical to a Physical Data Model (PDM) for enhanced database performance.
- Jul 13 min
Dimensional Modeling - Part 0: 4-Step Design Process
Data WarehouseDatabaseData EngineeringData ModelingThis article outlines a structured approach to Data Design, detailing essential steps for creating effective data models that align with business needs. It covers gathering business requirements, conducting collaborative workshops, and following the Four-Step Dimensional Design Process. The article also features a use case for modeling data in a Fast Food outlet and discusses managing changes in dimension data using Slowly Changing Dimensions (SCDs).
- Jun 3011 min
ER Modeling and Normalization
DatabaseData ModelingThis article covers Entity-Relationship (E-R) Modeling, which visually depicts the relationships between identifiable entities in a database. It discusses key concepts such as entities and their attributes, relationships and cardinality, and the importance of normalization (1NF, 2NF, 3NF) to optimize data structure and reduce redundancy for improved data integrity and efficiency.
- Jun 2912 min
Relational Database Management System
DatabaseData EngineeringThis article provides an overview of Relational Database Management Systems (RDBMS), covering key features such as data representation through tables, transaction principles (Atomicity, Consistency, Isolation, Durability), and concepts like primary and foreign keys. It highlights the importance of data integrity, security, normalization, and referential integrity in maintaining valid relationships between tables for effective data management.
- Aug 89 min
Dimensional Modeling - Part 2: Basic Dimension Table Techniques
Data WarehouseDatabaseData EngineeringData ModelingDimensional ModelingThe topics covered include Degenerate Dimension, Conformed Dimension, Role-Playing Dimension, Junk Dimension, Outrigger Dimension, and Slowly Changing Dimensions (SCD). The SCD category further delves into different types, such as Type 0 to Type 7, each with its unique approach to handling historical and changing data.
- Apr 213 min
Dimensional Modeling - Part 1: Basic Fact Table Techniques
Data WarehouseDatabaseData EngineeringData ModelingDimensional ModelingIn this article, I will introduce the concept of the Basic Fact table in Dimensional data modeling. To understand this technique, we will explore the different types of data modeling and recap some fundamental knowledge, including the star and snowflake schemas, and the concepts of normalization.