[#javax-jdo-annotation-NotPersistent]
= @NotPersistent (jdo)

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The `@javax.jdo.annotation.NotPersistent` annotation is used by JDO/DataNucleus to indicate that a property should not be persisted to the database.

Apache Causeway also uses this annotation, though (currently) only in the very minimal way to suppress checking of inconsistent metadata between JDO and Causeway annotations (eg `@Column#allowsNull()` vs `@Property#optionality()`, or `@Column#length()` and `@Property#maxLength()`).

[NOTE]
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The framework parses the `@NotPersistent` annotation from the Java source code; it does not query the JDO metamodel.
This means that it the `@NotPersistent` annotation must be used rather than the equivalent `<field>` link:http://www.datanucleus.org/products/accessplatform_4_0/jdo/fields_properties.html[XML metadata].

Moreover, while JDO/DataNucleus will recognize annotations on either the field or the getter method, Apache Causeway (currently) only inspects the getter method.
Therefore ensure that the annotation is placed there.
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