What do you mean by correlated subquery, Database Management System

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What do you mean by Correlated subquery?

Subqueries, or nested queries, are used to bring back a set of rows to be used by the parent query. Depending on how the subquery is written, it can be implemented once for the parent query or it can be implemented once for everyrow returned by the parent query. If the subquery is implemented for each row of the parent, this is known as correlated subquery.


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