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Course Overview

In today’s data-driven world, SQL (Structured Query Language) is the universal language of data. From analysts and engineers to product managers and business leaders, the ability to query, manipulate, and interpret data is no longer optional — it is a fundamental professional skill.

This free, self-paced SQL course is designed to build proficiency from the ground up. Starting with core database concepts and progressing through advanced functions, window analytics, performance tuning, and interview-ready theory, learners gain both the technical depth and practical fluency that employers demand.

Built around PostgreSQL — one of the most widely adopted open-source databases — the course uses real-world case studies, step-by-step demonstrations, and curated exercises to ensure every concept is understood and applied, not just memorised.

Course Highlights


6 comprehensive modules covering beginner to advanced SQL

Hands-on installation, setup, and case study walkthroughs

Full coverage of Joins, Subqueries, Views, and Indexes

String, Mathematical, Date-Time, and Window Functions

Interview-ready topics: Normalisation, ACID compliance, Primary & Foreign Keys

8 performance optimisation tips for real-world query efficiency

100% free — no payment, no barrier to entry


You Will Learn

Write and optimise SQL queries using PostgreSQL from scratch

Perform complex data filtering, aggregation, and conditional logic

Master all major JOIN types and combine datasets with set operations

Apply String, Mathematical, Date-Time, and Window functions to real datasets

Design normalised database schemas and understand ACID principles

Identify and resolve query performance bottlenecks using practical tips

Prepare confidently for SQL-based data interviews and assessments

Curriculum Structure

  • Course introduction and resources
  • Installation and setup demonstration
  • Case study walkthrough (Part 1 & 2)

  • Tables, DBMS, Types of SQL commands, and PostgreSQL
  • Basic SQL commands: CREATE, INSERT, SELECT, WHERE, UPDATE, DELETE, ALTER
  • Importing data from files; restoring and backing up databases

  • Filtering: IN, BETWEEN, LIKE
  • Ordering: ORDER BY, LIMIT
  • Aliases, Aggregate Commands, GROUP BY, HAVING
  • Conditional logic: CASE WHEN

  • Inner Join, Left Join, Right Join, Full Outer Join, Cross Join
  • UNION, INTERSECT, EXCEPT operations
  • Subqueries in WHERE, FROM, and SELECT clauses
  • Views and Indexes

  • String Functions: LENGTH, UPPER/LOWER, REPLACE, TRIM, CONCATENATION, SUBSTRING
  • Mathematical Functions: CEIL, FLOOR, ROUND, POWER, RANDOM
  • Date-Time Functions: CURRENT DATE/TIME, AGE, EXTRACT
  • Pattern (String) Matching and Regular Expressions
  • Data Type Conversion Functions and User Access Control
  • Window Functions: ROW_NUMBER, RANK, DENSE_RANK, NTILE, LAG, LEAD, RUNNING TOTAL

  • Tablespace, Primary Key, Foreign Key, ACID Compliance, TRUNCATE
  • Normalisation: 1NF, 2NF, 3NF/BCNF, 4NF, 5NF
  • 8 performance enhancement tips: EXPLAIN, VACUUM, String Functions, Joins, Schemas & more

Why SQL Skills Matter

SQL remains the most in-demand data skill across industries. Here’s why learning it can change your career trajectory:

  • SQL is consistently ranked the #1 most requested technical skill in data job postings globally, appearing in over 60% of data analyst and data engineer job descriptions.
  • Professionals with demonstrated SQL proficiency earn significantly higher salaries — data analysts with SQL skills command up to 30% higher compensation than peers without it.
  • According to Stack Overflow’s Developer Survey, SQL has been the most commonly used language for over a decade, used by more than 51% of professional developers worldwide.
  • PostgreSQL — the database used in this course — was ranked the most admired and desired database for the third consecutive year, reflecting its industry relevance and community trust.

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FAQs

This course is ideal for aspiring data analysts, business analysts, software developers, product managers, and anyone who works with data and wants to query, manipulate, and understand it using SQL. No prior technical background is required.

Yes. This is a completely free course with no hidden fees or paid upgrades. All modules, videos, and resources are available to enrolled learners at no cost.

The course is built on PostgreSQL, one of the most widely adopted and powerful open-source relational databases. The installation and setup module walks you through getting started from scratch.

Unlike many introductory courses that stop at basic SELECT statements, this program goes deep — covering Window Functions, Regular Expressions, Normalisation theory, ACID compliance, and real-world performance optimisation tips that prepare you for professional environments and interviews.

Yes. The course includes a multi-part case study that demonstrates how SQL is applied to solve practical business problems, from initial data setup to complex analytical queries.

Absolutely. The final module is specifically dedicated to interview-relevant concepts including Normalisation (1NF through 5NF), Primary and Foreign Keys, ACID compliance, and query performance tips — topics that frequently appear in data engineering and analyst interviews.

No prior programming experience is necessary. The course begins from the very basics — explaining what a database is, how SQL works, and building up knowledge progressively. Learners with some experience will also benefit from the advanced modules.

The course is self-paced, so you can progress at your own speed. Depending on your availability, most learners complete it within 4–6 weeks dedicating a few hours per week. The modular structure makes it easy to learn in short, focused sessions.
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