Common Table Expressions (CTEs)

Summary

A WITH clause that names a temporary result set for readability — functionally similar to a subquery, but far easier to read and reuse within a long, complex query.

• 1Rewrite a nested subquery from the previous topic as a CTE and compare readability.
• 2Practice chaining 2-3 CTEs together in a single query.
• 3Adopt CTEs as your default for any query beyond a couple of joins.