What is a Common Table Expression (CTE) and how do you use them?

We've had some questions about what a Common Table Expression (CTE) is. Patrick describes what they are and how you can use them in SQL Server or Azure Synapse Analytics

More about A Common Table Expression (CTE)

A Common Table Expression (CTE) is a temporary named result set or table that exists in the database for a limited time. It can be used to break down complex queries into simpler parts, allowing you to refer back to previously defined tables and columns without repeating them. You use CTEs by writing an expression after the keyword WITH. This expression defines the name of the CTE, followed by its column definitions and their data types, and then finally a query which populates it with data. The CTE can then be referenced like any other table in subsequent queries within the same statement.

More links on about Power Platform/Power BI

• Common Table Expressions: When and How to Use Them

A Common Table Expression (CTE) is the result set of a query which exists temporarily and for use only within the context of a larger query. Much like a derived ...

• Common Table Expressions - The Ultimate Guide

May 21, 2022 — A CTE (Common Table Expression) is a temporary result set that you can reference within another SELECT, INSERT, UPDATE, or DELETE statement.

• WITH common_table_expression (Transact-SQL) - SQL Server

4 days ago — Specifies a temporary named result set, known as a common table expression (CTE). This is derived from a simple query and defined within the ...