· intermediate
Data Manipulation in SQL
Name your intermediate steps with CTEs, then rank, compare and accumulate rows with window functions. This is where SQL stops being a filter and becomes an analysis language.
Written in house, from the work rather than from a syllabus. Every example is one we would use ourselves, and every exercise is checked against the same engine that grades your answer.
What you’ll learn
- Replace nested subqueries with readable named CTEs
- Explain how a window differs from a group
- Rank rows and pick the top N per category
- Compare a row with the one before or after it
- Build running totals and moving averages with window frames
Before you start
- · Intermediate SQL, or comfort with subqueries and GROUP BY
- · Familiarity with joins