May 22, 2024 · SQL has an ability to nest queries within one another. A subquery is a SELECT statement that is nested within another SELECT statement and which return intermediate results. SQL executes innermost subquery first, then next level. See the following examples :

Statements that include a subquery usually take one of these forms: WHERE expression [NOT] IN (subquery) WHERE expression comparison_operator [ANY | ALL] (subquery) WHERE [NOT] EXISTS (subquery) Check for more subquery rules and subquery types. More examples of Nested Subqueries.

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.

May 7, 2020 · Nested queries allow you to perform operations that would be difficult or impossible with a single SELECT statement. They enable you to break down complex problems into simpler sub-tasks, making your queries more manageable and efficient.

Apr 11, 2025 · Nested queries, also known as subqueries, are an essential tool in SQL for performing complex data retrieval tasks. They allow us to embed one query within another, enabling us to filter, aggregate, and perform sophisticated calculations.

A subquery is a query that is nested inside a SELECT, INSERT, UPDATE, or DELETE statement, or inside another subquery. The code samples in this article use the AdventureWorks2022 or AdventureWorksDW2022 sample database, which you can download from the Microsoft SQL Server Samples and Community Projects home page.

Oct 4, 2022 · SQL admins usually use subqueries inside the WHERE clause to narrow down the result of the main query (or outer query). You usually put subqueries inside brackets and you can use them with comparison operators such as =, <, >, <=, and >=.

Jan 31, 2024 · In this tutorial, we will learn about the Nested query with multiple SELECT statements nested together. In SQL, a Nested SELECT query is a way to perform complex queries by nesting a query inside another.

Mar 25, 2025 · A SQL subquery, otherwise known as a nested SQL query, is a query within another query that helps filter, transform, or aggregate data before passing the results to the main query. We can use subqueries in SELECT , INSERT , UPDATE , and DELETE statements as well as WHERE , FROM , and HAVING clauses.

Summary: In this tutorial, you’ll learn how to use SQL subqueries to form flexible queries for retrieving data from the database. A subquery is an SQL query nested inside another query. The query that contains a subquery is known as an outer query. To write a subquery, you need to have a deep understanding of the SELECT statement: select_list.