• views: 134
• date: 6 May 2026
• posted by: 0nelove

Core SQL Concepts
JOINS
Window Function
Common Table Expression and Subqueries
Performance basics
Requirements
Basic understanding of SQL
Description
We dive into core SQL concepts—joins, aggregations, filtering. You'll tackle window functions, which is where most developers fall apart. These aren't optional if you want to write efficient, modern SQL. You'll learn how to analyze data without destroying performance or writing messy nested queries.Then comes Common Table Expressions (CTEs)—not just syntax, but when and why to use them. You'll understand how to structure complex logic cleanly instead of stacking unreadable subqueries that no one (including you) can maintain later.Finally, we get into performance fundamentals, especially indexing. This is where the difference between a beginner and a serious engineer becomes obvious. If you don't understand indexing, you are guessing—not optimizing. You'll learn how queries actually execute and why some queries that look "simple" are disastrously slow.This course earns you confidence in SQL concepts. After completing this day wise course you will feel the upgrade!By the end of this course, you won't just write SQL that works—you'll write SQL that is intentional, efficient, and scalable.SELECT statement deep diveWHERE, AND, OR, NOT conditionsORDER BY, DISTINCTAggregate functions (COUNT, SUM, AVG, MIN, MAX)GROUP BY and HAVINGJoins (INNER, LEFT, RIGHT, FULL)Subqueries (basic + correlated)Window FunctionsNormalisation
Beginner Data Engineer



   
   
   

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