Watch out for Unsynchronized Entities

One thing to watch out for when updating entities like this, is that the EntityManager may contain outdated entities after the query has executed. This could be the case if your JPA provider uses a cache (such as Hibernate’s second level cache), or if there are changes that are pending to be flushed. As a result, the state of the entities in the EntityManager may not be accurate. This would be the case if an entity affected by the update query is referenced in the EntityManager. One may wonder why the EntityManager is not just cleared after executing the query to avoid this inconsistency, but the reason for this is that there might be changes that have not yet been flushed, that would then be lost. However, you do get the option of configuring this by setting the clearAutomatically attribute of the @Modifying annotation to true.

@Table(uniqueConstraints = [UniqueConstraint(columnNames = ["unique_column"])])