Finally, we use the SELECT statement to select appropriate columns from the CTE as if it were a regular table. In the parentheses, we select the columns we want to include in the CTE and specify the conditions for the query in the WHERE clause. This CTE starts with the keyword WITH and the name of the CTE, top_5_sales_employees. The tables we will be using in this example are called employees (includes the columns employee_id, employee_name, and salary) and purchase(contains the columns id, date, customer_id, and total_amount). Let’s say you wanted to write a query that returns the purchases managed by the five employees with the highest salary in the Sales department. You can think of a CTE as a temporary view that you can reference in the outer query, as we’re doing in the above example. The rest of the query (the outer query) can refer to the CTE and its columns as if the CTE were a regular table. This CTE selects some columns ( column1, column2. The first thing we are doing is giving our CTE a name, cte_name. A CTE begins with the WITH clause, followed by the name of the CTE and the SELECT statement that defines it. Basics of CTEs in SQL Serverįirst, let's review the basics of CTEs. It will teach you how to master the most challenging type of query and effectively organize long SQL queries. In this article, we'll start with standard CTE syntax and then explore how to write recursive CTEs in SQL Server.Ī great way to further your understanding of recursive CTEs is to take our course on Recursive Queries in MS SQL Server.
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