02 β Relational Databases (RDBMS)
Relational databases are the backbone of most critical systems. This module makes you fluent in concepts and key engines.
π Overview
- Understand the relational model and SQL
- Learn how major RDBMS engines differ
- Be able to design and query relational schemas confidently
π§± Core Concepts
[[Concepts]]
- Understand tables, rows, columns, and relations
- Learn keys: primary, foreign, composite, candidate
- Know normal forms (1NF, 2NF, 3NF, BCNF) and when to denormalize
- Differentiate between OLTP and OLAP workloads
π Major Engines
[[PostgreSQL]]
- Install and connect to a PostgreSQL instance
- Create tables, define constraints, and write basic to advanced SQL queries
- Explore indexes, views, materialized views, and extensions
[[MySQL]]
- Understand MySQLβs role in web and startup ecosystems
- Learn differences between InnoDB and MyISAM (and why InnoDB is default)
- Practice indexing and query tuning basics
[[Oracle]]
- Understand where Oracle is typically used (large enterprises)
- Get a sense of Oracle-specific features (PL/SQL, advanced partitioning)
[[SQL Server]]
- Understand Microsoft SQL Server ecosystem
- Learn about T-SQL, tooling, and common deployment patterns
[[SQLite]]
- Understand where SQLite fits (embedded, mobile, local apps)
- Learn its limitations and strengths as a serverless DB
π Connections
- Connect RDBMS topics with:
- [[01 - Fundamentals]] β ACID, transactions, indexing, query optimization
- [[07 - Data Modeling]] β relational modeling patterns
- [[04 - Big Data]] β when you outgrow a single RDBMS node