What is a recursive CTE and when is it used?
Model answer
A CTE that refers to itself, with an anchor query and a recursive part combined by UNION ALL, until no new rows appear. It is used for hierarchies such as employee-manager trees, categories and bill of materials. Add a depth limit to avoid endless loops.
Learn this topic
Subqueries, EXISTS and CTEs: Queries Inside Queries in the course SQL for Beginners: Learn Databases Step by Step.
Sign in to add your own answer.