SQL Fundamentals Basic Introduction to basic of querying tables in relational databases joining tables into one, combining tables using set theory, work with subqueries in PostgreSQL BASIC2 how to use CASE WHEN to create categorical variables aggregate data into single column with multiple filtering construct subqueries using SELECT, FROM, WHERE nested and correlated subqueries to extract more complex data from a relational database common table expressions Intermediate Intro to windows functions fetching,ranking, paging aggregate window functions and frames pivoting, roll-up and cube COALESCE and STRING_AGG