HHH-12716 - Sample code is required for documentation of disabling polymorphism in queries
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@ -968,14 +968,20 @@ include::{sourcedir}/HQLTest.java[tags=hql-polymorphism-example, indent=0]
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This query names the `Payment` entity explicitly.
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However, all subclasses of `Payment` are also available to the query.
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So if the `CreditCardPayment` and `WireTransferPayment` entities extend the `Payment` class, all three types would be available to the entity query,
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So, if the `CreditCardPayment` and `WireTransferPayment` entities extend the `Payment` class, all three types would be available to the entity query,
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and the query would return instances of all three.
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This behavior can be altered in two ways:
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- by limiting the query to select only from the subclass entity
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- by using either the `org.hibernate.annotations.Polymorphism` annotation (global, and Hibernate-specific). See the <<chapters/domain/inheritance.adoc#entity-inheritance-polymorphism, `@Polymorphism` section for more info about this use case>>.
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[NOTE]
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====
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This can be altered by using either the `org.hibernate.annotations.Polymorphism` annotation (global, and Hibernate-specific) or limiting them using in the query itself using an entity type expression.
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The HQL query `from java.lang.Object` is totally valid (although not very practical from a performance perspetive)!
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The HQL query `from java.lang.Object` is totally valid! It returns every object of every type defined in your application.
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It returns every object of every entity type defined by your application mappings.
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====
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[[hql-expressions]]
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