In this tutorial, you'll learn about SQL subquery, a query nested within another query, to form flexible queries.

Apr 14, 2025 · What is SQL Subquery? In SQL, a subquery can be defined as a query embedded within another query. It is often used in the WHERE, HAVING, or FROM clauses of a statement. Subqueries are commonly used with SELECT, UPDATE, INSERT, and DELETE statements to achieve complex filtering and data manipulation. They are an essential tool when we need to ...

Feb 13, 2025 · What is subquery in SQL? A subquery is a SQL query nested inside a larger query. A subquery can be located in: - A SELECT clause - A FROM clause - A WHERE clause - A HAVING clause; The subquery can be nested inside a SELECT, INSERT, UPDATE, or DELETE statement or inside another subquery.

Aug 3, 2021 · This article illustrated how to write a subquery in SQL within the SELECT, FROM, and WHERE clauses. Even if this ability is interesting in structured Query Language (SQL), developers should use it carefully since it may affect the query performance.

The objective of this SQL Server tutorial is to teach you how to use a SUBQUERY in a SQL statement to expand the scope of operation of the statement and to narrow its focus with respect to the output and get more specific output.

Jan 2, 2025 · In this article, We will learn about Subquery in a SELECT statement by understanding various examples and output in detail. A subquery (also known as a nested query or inner query) is a query placed inside another query. The subquery returns a result that is used by the outer query.

Mar 25, 2025 · In this query: The subquery is executed first. It searches the departments table and returns the department_id of the ‘Sales’ department.; Next, the outer query is executed. It retrieves the department_id returned by the subquery and returns all employees whose department_id matches with the retrieved one.; This is how queries, including subqueries, are executed in SQL.

SQL subqueries are queries inside another query.

Dec 28, 2023 · In this article let us see what is a subquery, where it can be used, and how to build a subquery. A subquery is a 'Select' query placed inside another query or SQL statement. A subquery can be used with a SELECT, INSERT, UPDATE, or DELETE statement and is generally placed within a WHERE, HAVING, or FROM clause of the outer or main query.

Summary: in this tutorial, you will learn about the SQL Server subquery and how to use the subquery for querying data. A subquery is a query nested inside another statement such as SELECT, INSERT, UPDATE, or DELETE. Let’s see the following example. Consider the orders and customers tables from the sample database.