What you'll learn

Teams rely on accurate summaries and comparisons to make decisions from data. Aggregating data incorrectly can lead to misleading or meaningless results.

In this course, Group and Aggregate Data with SQL in PostgreSQL, you’ll learn how to group, summarize, and analyze data correctly using PostgreSQL.

First, you’ll explore core aggregate functions and understand how grouping reshapes result sets and affects NULL handling. Next, you’ll apply GROUP BY and conditional aggregation using CASE expressions and PostgreSQL’s FILTER clause, while learning where GROUP BY breaks down. Finally, you’ll use window functions to perform comparisons, rankings, and running calculations without losing row-level detail, and apply validation techniques to ensure your results make sense.

When you’re finished with this course, you’ll have the skills and judgment needed to use aggregation and window functions confidently for real-world analytics in PostgreSQL.