1. Congratulations
Congratulations, you've covered a lot of ways to improve your queries in this course.
2. Chapter 1: ways to combine data
In chapter one, you learned multiple ways to combine data, including the functionally equivalent joins and subqueries. You learned about CTEs. You learned how temporary tables are useful when working with large data.
3. Chapter 2: limiting the results
In chapter two, you found that SQL has an order of operations. This helped you understand the impact of filtering in both the WHERE clause and the JOIN clause. You also learned to be wary of joining tables of differing granularities.
4. Chapter 3: learning the database
In chapter three, you focused on table and database properties using pg_tables and the information_schema. You learned the difference between tables and views and found the impacts of row versus column-oriented storage. You sped up your queries by using indexes and partitions.
5. Chapter 4: using the query planner
Finally, you learned about the query lifecycle, focusing on the query planner and optimizer. You visualized the steps in the query plan with EXPLAIN and spent time exploring how all the prior query structure choices impacted the final query plan.
6. Thank you!
It has been a pleasure working with you, and I wish you the best of luck in using the tools from this course to improve your SQL.