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SQL vs NoSQL: How to Choose in System Design
Compare SQL vs NoSQL for system design: data modeling, transactions, scale, trade-offs, and the right database for each workload.
21 min read
Structured learning path
Database Fundamentals
Follow this series from the first concept to the final deep dive. Every article is arranged in the recommended reading order.
Start with article 1- Articles
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- 221 min
Your path
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10 focused lessons
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- Read 2
Database Indexing Explained: SQL Examples and Interview Questions
Learn database indexing with SQL examples: B-tree indexes, query plans, composite index order, write costs, and interview questions.
20 min read - Read 3
What Is Database Connection Pooling and Why It Matters
Learn what database connection pooling is, how it works under the hood, and why it is essential for building performant, scalable backend applications.
34 min read - Read 4
How ORMs Work Internally: A Simple Explanation
Learn how Object-Relational Mappers work under the hood - from query building and identity maps to lazy loading and the N+1 problem.
35 min read - Read 5
What Is a Database Transaction? Step-by-Step Guide
Learn what a database transaction is, how BEGIN, COMMIT, and ROLLBACK work, and when to use savepoints with clear SQL examples.
24 min read - Read 6
ACID Properties Explained: Atomicity, Consistency, Isolation, and Durability
Learn what ACID properties mean in databases. Understand atomicity, consistency, isolation, and durability with simple examples and real-world use cases.
21 min read - Read 7
Database Normalization Explained: 1NF, 2NF, and 3NF with Examples
Learn database normalization step by step. Understand 1NF, 2NF, and 3NF with clear table examples and how each normal form reduces redundancy.
16 min read - Read 8
Basic SQL Queries Every Developer Must Know
Learn the essential SQL queries every developer needs: SELECT, WHERE, JOIN, GROUP BY, INSERT, UPDATE, and DELETE with real examples.
20 min read - Read 9
Primary Key vs Foreign Key Explained with Examples
Primary key vs foreign key explained with SQL examples, core differences, and best practices to design reliable relational database schemas.
12 min read - Read 10
Relational Databases Explained: Tables, Rows, and Keys
Learn relational databases: tables, rows, columns, and keys - with practical SQL examples and clear explanations for beginners.
18 min read