Master the most challenging type of SQL queries. Learn how to process trees and graphs in SQL, and how to effectively organize long SQL queries.
Common Table Expressions (CTEs), often simply called WITH clauses, are essentially just named subqueries. They are a fairly new feature of SQL; with CTEs, you can break a long query into smaller chunks, which makes it more readable. Unlike SQL subqueries, CTEs can be recursive, allowing the traversal of hierarchical models of enormous depth.
About the Common Table Expressions in SQL Course
This course will cover simple CTEs, nested CTEs, and recursive CTEs. You will learn how to manage your SQL queries with CTEs, how and when to nest CTEs, and how to use recursive CTEs to move through hierarchical data models.
This course is intended for intermediate users. We assume the user knows the basics of SQL, including:
Test your knowledge of SQL
Your first encounter with Common Table Expressions
You'll get to know how to use nested CTEs
You'll find out what recursion is and how to use it in SQL queries
The very basics
Processing trees with recursive CTE
Processing graphs with recursive CTE
You'll get to know how to use INSERT, DELETE, UPDATE statements with CTEs
CTEs with data modifying statements
Test your knowledge in this final quiz