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SQL and Databases

Build robust database query skills. Learn relational database design, query optimization, joins, aggregation, and filtering across PostgreSQL, MySQL, and SQLite.

3 tutorials published•Updated monthly by the technical editorial team

Published Guides in SQL and Databases

3 articles

Beginner7 min read

SQL Basics for Beginners: Relational Database Fundamentals

A gentle, comprehensive introduction to Structured Query Language (SQL). Master database concepts, primary keys, and essential querying commands.

Key Highlights:

Understand what a Relational Database Management System (RDBMS) is

Learn table schema structure: rows, columns, data types, and primary keys

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Beginner8 min read

SQL SELECT, WHERE and ORDER BY: Filtering & Sorting Data

Learn how to filter and sort database records with precision. Explore comparison operators, AND/OR logic, LIKE wildcards, and ORDER BY clauses.

Key Highlights:

Filter rows with precision using the WHERE clause and comparison operators

Combine multiple conditions using logical AND, OR, and NOT operators

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Intermediate10 min read

Understanding SQL Joins: INNER, LEFT, RIGHT and FULL Explained

Master SQL table joins with practical visual analogies. Learn how and when to use INNER JOIN, LEFT OUTER JOIN, and multi-table joins without performance degradation.

Key Highlights:

Understand database normalization and the purpose of Foreign Keys

Distinguish between INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL OUTER JOIN

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Applied Practice

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