SQL Window Functions: Master Ranking, Aggregation, and Navig

This course is designed to help you master SQL window functions step by step, even if you are still building confidence with SQL. Window functions are one of the most powerful features in SQL because they allow you to perform advanced analysis without collapsing your data into a single summary row. Instead, you can compare values across rows, calculate running totals, rank records, find previous or next values, and analyze trends with much more flexibility.

In this course, you will learn how to use the most important window function concepts, including PARTITION BY, ORDER BY, ranking functions, aggregate window functions, and value/navigation functions. You will understand how each function works, when to use it, and how it solves real-world data problems. Every topic is explained in a clear and practical way, with examples that help you build both understanding and confidence.

Functions covered in this course

• ROW_NUMBER()

• RANK()

• DENSE_RANK()

• NTILE()

• SUM() OVER

• AVG() OVER

• COUNT() OVER

• MIN() OVER

• MAX() OVER

• LAG()

• LEAD()

• FIRST_VALUE()

• LAST_VALUE()

• NTH_VALUE()

You will also practice writing SQL queries that are useful in business, reporting, and data analysis tasks. For example, you will learn how to assign rankings to sales records, calculate cumulative totals, compare the current row with previous rows, and extract the first, last, or nth value in a dataset. These skills are highly valuable for data analysts, SQL learners, and anyone who wants to write more advanced and professional queries.

By the end of this course, you will be able to use window functions effectively in your own SQL projects and analytical work. Whether you are learning SQL for data analysis, reporting, or career development, this course will give you a strong practical foundation in one of SQL’s most important topics.