Oracle Subqueries
Version 19.2.0.1

General Information
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Purpose Subqueries, in Oracle, are nothing more than queries within queries and they can be present in the SELECT, FROM, WHERE, GROUP BY, HAVING, and ORDER BY clauses. Subqueries can not only be used essentially anywhere they come in a wide number of variations many of which are named such as SIMPLE, CORRELATED, SCALAR, INLINE, and NESTED.

Examples of subqueries can be found throughout the Library but the following links point to places in the Library where you are going to find specific examples of subquery usage that should acquaint you with most of the constructs.

Related Topics
EXISTS Condition
Inline Views
Membership Conditions (IN and NOT IN)
SELECT Statements
What's New In 18cR3
What's New In 19cR2

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