A common table expression, also known as a CTE, is a temporary named result set in SQL that can be used within a SELECT, INSERT, UPDATE, or DELETE statement. It is defined using the WITH keyword, and can be thought of as a temporary view or inline table-valued function.

One of the primary advantages of using a common table expression is that it allows you to break complex queries down into smaller, more manageable pieces. This makes it easier to write and read the query, as well as to understand and troubleshoot any issues that may arise. In addition, a CTE can improve query performance by allowing the query optimizer to better understand the underlying data and generate more efficient execution plans.

Another advantage of using a common table expression is that it can be used to create recursive queries. This means that the CTE can reference itself, allowing you to perform complex operations such as traversing a hierarchical data structure or performing arbitrary computations.

In summary, a common table expression is a powerful and flexible tool in SQL that allows you to define and use temporary named result sets within a query. It can help you write cleaner and more efficient queries, and enables you to perform complex operations such as recursive queries.

https://stevestedman.com/cte-class

More from Stedman Solutions:

Steve and the team at Stedman Solutions are here for all your SQL Server needs.
Contact us today for your free 30 minute consultation..
We are ready to help!