Active 9 years, 11 months ago. Viewed 5k times. Improve this question. Jeriho Jeriho 6, 9 9 gold badges 39 39 silver badges 56 56 bronze badges. Add a comment. Active Oldest Votes. From there: To avoid this problem we recommend using the "semi"-unique attributes of your persistent class to implement equals and hashCode.
Improve this answer. Matthew Farwell Matthew Farwell Don't see the evidence that Hibernate do uses equals and hashCode in this cite and at the page — Lu Victor Sorokin Victor Sorokin Sign up or log in Sign up using Google.
Vlad Mihalcea. Leave a Comment Posted on October 23, by vladmihalcea. Insert details about how the information is going to be processed. Leave a Reply Cancel reply Your email address will not be published. Find Article Search. Video Course. Hypersistence Optimizer. ERP Contact. By continuing to use this website, you agree to their use. But then, it implies that you fetched that large collection from the database.
The performance penalty of fetching such a collection from the database is multiple orders of magnitude higher than the single bucket overhead. You use queries for those instead. But then, for small collections. For bidirectional associations, List s perform better anyway. Mark has written a blog post to justify his beliefs. In his article, Marks says that the database-generated identifier equality implementation does not work for merge or getReference.
How to implement equals and hashCode using the JPA entity identifier primary key article demonstrates that this equals implementation works for detached objects. That was the whole point of coming up with such an implementation. We want it to work across all entity state transitions. And with the equality implementation method that I offer you, you can use it safely. Not only that you should NOT avoid mixing detached and managed entities, but this is actually a great feature that allows you to hold on detached objects, and therefore prevent lost updates in long conversations.
At least not as long as they are managed. Hibernate strives to deliver strong consistency. Viewed 5k times. Improve this question. Jeriho Jeriho 6, 9 9 gold badges 39 39 silver badges 56 56 bronze badges. Add a comment. Active Oldest Votes. From there: To avoid this problem we recommend using the "semi"-unique attributes of your persistent class to implement equals and hashCode.
Improve this answer. Matthew Farwell Matthew Farwell Don't see the evidence that Hibernate do uses equals and hashCode in this cite and at the page — Lu Victor Sorokin Victor Sorokin Sign up or log in Sign up using Google. Sign up using Facebook.
0コメント