Quantified predicate subqueries can be correlated subqueries.
This example of a correlated subquery in the having clause of an outer query finds the types of books in which the maximum advance is more than twice the average within a given group:
select t1.type from titles t1 group by t1.type having max(t1.advance) >= any (select 2 * avg(t2.advance) from titles t2 where t1.type = t2.type)
type ---------- mod_cook (1 row affected)
The subquery above is evaluated once for each group that is defined in the outer query, that is, once for each type of book.
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