In JPA, I am confused when to use the attribute optional=false and the annotation @Column(nullable=false). What is the difference?
In JPA, I am confused when to use the attribute optional=false and the annotation
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In JPA, I am confused when to use the attribute optional=false and the annotation @Column(nullable=false). What is the difference?
@Column(nullable=false)is an instruction for generating the schema. The database column generated off the class will be marked not nullable in the actual database.optional=falseis a runtime instruction. The primary functional thing it does is related to Lazy Loading. You can’t lazy load a non-collection mapped entity unless you remember to set optional=false (because Hibernate doesn’t know if there should be a proxy there or a null, unless you tell it nulls are impossible, so it can generate a proxy.)