SQL + Data Engineering Foundations

SQL helps you turn questions about data into clear, repeatable queries. This playlist teaches you how to retrieve, combine, and analyse data, then connects those skills to database design, query performance, and the decisions involved in running databases as applications grow.

The syllabus covers 21 modules and 249 learning items, combining concept lessons, practice problems, and situation-based interview questions. You will move from SQL basics to advanced querying, then explore the database foundations that support backend development, data analysis, and data engineering.

What You Will Learn

Start with database and table basics, data types, keys, constraints, and SQL commands. Learn to filter and sort records, group data, calculate aggregates, and use conditional logic, string functions, and date functions.

Build on these foundations with joins, set operations, subqueries, common table expressions, and window functions. You will also work through data modification, transactions, access control, and JSON operations in SQL.

Later lessons cover schema design, normalization, query debugging with EXPLAIN, indexes, and how data is stored. Continue with read scaling, sharding, distributed IDs, schema changes, partitioning, and data lifecycle management.

Understand the Result Your Query Produces

A query needs to answer the intended question correctly. You need to decide which rows belong in the result, how tables should be joined, how NULL values affect the answer, and whether grouping or a window function fits the task.

As you progress, connect correctness with performance. Learn to examine how a query runs and how table design, keys, and indexes influence the work a database must do.

Learn Through Queries and Practical Scenarios

Practise with problems involving customer orders, employee salaries, sales summaries, user activity, rankings, and continuous date ranges. The syllabus also includes 15 interview situations grouped into easy, medium, and hard sections.

• Translate a question about data into filtering, joining, grouping, or ranking steps.
• Work through practice problems as new SQL concepts are introduced.
• Use subqueries, CTEs, and window functions to express more involved logic.
• Review query results for duplicates, missing records, NULL values, and boundary cases.
• Connect query performance to schema design, storage, and indexing decisions.

Who Is This Playlist For?

This playlist is suitable for beginners learning SQL, students preparing for placements, and developers or analysts strengthening their database skills. It starts with database fundamentals and setup, so previous SQL knowledge is not required. Familiarity with tables, basic logic, and programming will help as the examples become more involved.

Prepare for SQL and Database Interviews

By the end, you should be able to write and explain SQL queries, choose suitable query techniques, and reason about database design and performance. Build your SQL interview preparation around checking correctness, explaining alternatives, and handling changes to a question. These skills support technical interviews for software engineering, data analysis, and data engineering roles.