I am using hibernate JPA implementation in our code. I want to perform soft delete of entity using JPA. I know for soft delete, hibernate provides #SQLDelete annotations. But I am looking for JPA specific solution. Is there any JPA specific solution for soft delete of entity?
Related
I am migrating a old project to a new tech stack without changing the database model(I know that is bad but no option). So I already have a audit table defined which has data as well.
Can I use the same audit table with Hibernate envers audit framework?
For other CRUD operations I am using spring data JPA.
what would be the best option for auditing? I want to audit delete as well.
You can not use existing audit tables as Audit tables created by envers have a specific format. If your existing audit tables follow the same pattern then you can use envers annotations to map table name and column names of your audit tables to envers tables.
You can refer docs for more info.
I am working on a project where I need to create history of particular table automatically. I have used #Audited annotation for it but it's creating duplicate data in table.
I am running out of space due to duplicate data.Even EclipseLink is not sloving my problem.
You tagged your question with Hibernate, but if switching to Eclipselink would be an option for you, be sure to check out the History Policy feature of Eclipselink. It allows automatic historization of data.
Please check Hibernate Envers.
This component integrates with JPA and Hibernate, and takes care of maintaing a revision history for any #Audited annotated Entity.
There are some guides on the net:
Maintain the data versioning info with Spring Data — Envers
Spring Boot : How to add JPA and Hibernate Envers Auditing
Spring Boot + Hibernate + Hibernate Envers
I want to use a many-to-many relation between System & Device. I want the system to know its devices order.
I've seen here that I can do it using #OrderColumn.
How can I do it using hibernate xml configuration instead of annotation?
If you're using Hibernate you could try with
sort="unsorted|natural|comparatorClass"
order-by="column_name asc|desc"
as attributes of your relatonship declaration
#OrderColumn is the JPA annotation introduced in JPA 2.0. This works as an additional feature if we work hibernate through JPA. There is no equivalent replacement in hibernate who work with hibernate directly.
Recently I faced a F-to-F interview in a company.
Interviewer just asked me the following question:
What are the differences between JPA's EntityManager and Hibernate's First level caching?
Please explain with suitable example.
Hibernate itself implemented JPA through the Hibernate Annotations and Hibernate EntityManager libraries (or flavors), which are built on top of the Hibernate Core libraries. Hibernate EntityManager is a complete implementation of JPA and it follows the JPA lifecycle
JPA is like an interface which is implemented by other ORM's and these ORM's are act as a vendor for this..
So, there is no question of difference...
and for to learn more you can go through this link.
https://blogs.oracle.com/carolmcdonald/entry/jpa_caching
It's actually hard to point the differences between those two as it's the same as asking the differences between a banana and an apple. Here are the definition of both.
Entity Manager
The EntityManager API is used to access a database in a particular unit of work. It is used to create and remove persistent entity instances, to find entities by their primary key identity, and to query over all entities. This interface is similar to the Session in Hibernate.
from http://docs.jboss.org/hibernate/entitymanager/3.5/reference/en/html/architecture.html
First Level Hibernate cache
It's a cache facility attached to the Hibernate session to speed up data retrieval.
Here is a good article about it that cover some basic aspects.
http://howtodoinjava.com/2013/07/01/understanding-hibernate-first-level-cache-with-example/
So, I would list some of the differences as:
Entity Manager is part of the JPA specification (which consequently is standard across the whole Java EE platform.) to perform database access via managed entities.
Hibernate First level cache is a cache facility to return cached hibernate entities (please note the bold as hibernate entities might not be the same JPA entities).
I have been looking at Hibernate Envers for entity auditing. I'm using EclipseLink but I'd like something similar.
I've seen some implementations that involve creating a SessionCustomizer to handle some of the persistence of auditing data. I'd really like something like Hibernate where I can simply annotate the entity and have the same effect.
Unfortunately, EclipseLink doesn't have a feature which covers auditing out-of-the-box.
We use a SessionEventListener to intercept a flush or commit and use the calculated changeset for inserting the auditing data into audit tables.
There is support for auditing of entities in EclipseLink. They call it History.
http://wiki.eclipse.org/EclipseLink/Examples/JPA/History