What are correlated subqueries in SQL?

Name: SQL Correlated Subqueries Part 1
Uploaded: 2021-11-15 03:52:53
Description: A correlated subquery is a subquery that references the same table as its containing query. In this tutorial, we'll walk through two common examples of using a correlated subquery with SQL.

Question

Accepted Answer

A correlated subquery (also known as a synchronised subquery) is a subquery (a query nested within another query) that leverages values from the outer query in a SQL database query. It can be slow since the subquery may be evaluated once for each row processed by the outer query.

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SQL Correlated Subqueries Part 1

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SQL Correlated Subqueries Part 3

SQL Correlated Subqueries Part 4

SQL Correlated Subqueries Part 5

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