42 words
Basic.optional - JPA annotation element
Annotation Elementjavax.persistence.Basic
boolean optional
(Optional) Defines whether the value of the field or property may be null.
This is a hint and is disregarded for primitive types; it may
be used in schema generation.
If not specified, defaults to
true.- Default value:
- true
- Since:
- JPA 1.0
This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
Object DB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.
Which JPA is Faster?
See a comparison of Hibernate, EclipseLink, OpenJPA, DataNucleus, MySQL, PostgreSQL, Derby, HSQLDB, DB4O by Versant, H2 Database, SQLite and ObjectDB
in the JPA Benchmark.
