52,214 questions
0
votes
1
answer
25
views
Why can CrudRepository.findById() return a Hibernate proxy?
It seems that findById() and manual queries in Spring repositories can return Hibernate proxies instead of real objects if these objects have been "loaded" earlier as lazy fields of other ...
- 51
0
votes
1
answer
64
views
Fix IllegalArgumentException for params in JPA
In JPA, I am trying to search the table with two optional fields say one and two which can be null at times. I have the controller and the repo like below.
class Some{
private SomeRepo someRepo;
...
- 129
0
votes
0
answers
19
views
Jakarta EclipseLink - how to keep bidirectional one to many relationship in sync using EntityManager
I have two classes:
@Entity
@Getter
@Setter
public class A {
@Id
private String aid;
@OneToMany(mappedBy = "mya")
private Collection<B> bees;
public ...
- 811
0
votes
0
answers
35
views
Why does Hibernate persist OneToOne entities in the wrong order, causing a foreign key constraint violation when saving nested entities?
I'm having a problem with the Jakarta Persistence API in my Spring Boot project. I'm relatively new to this, so I apologize if this is something really basic.
Here is a simplified version of my ...
0
votes
0
answers
26
views
Eclipse persistence and DB2 - JPA query needs `With UR`
I'm using eclipse persistence and have a method that generates a select query to get a list.
I need to have this query use the equivalent of with UR to prevent locking issues.
I have tried all kinds ...
- 11.5k
0
votes
0
answers
34
views
Why PersistenceException is thrown rather than EntityExistsException while trying to persist the same entity twice
I have set up a very simple Java web project (using NetBeans' Web Application template). It is deployed on Payara 6.2025.7 with a H2 database as a JTA data source.
I can't get EntityExistsException ...
- 811
1
vote
0
answers
27
views
Spring Data JPA find() method triggers insert [duplicate]
I'm building an application using Spring Data JPA and Hibernate. I encountered unexpected behavior: when I'm calling a findBySomeId() method on a repository, it triggers a SQL INSERT on an associated ...
- 121
0
votes
1
answer
21
views
SemanticException in subquery after upgrading hibernate version from 5.2.14 to 6.6.5
I've run into a problem with a subquery after upgrading my application from hibernate version 5.2.14 to 6.6.5. When running the query, I get a org.hibernate.query.SemanticExpression.
I created a ...
- 175
0
votes
0
answers
23
views
what are the usage differences between optimistic locking and Isolation levels?
optimistic lock and isolation levels have the same concepts in integrity of transactions. my question is when i should use different isolation levels instead of optimistic locking for achieving ...
- 123
0
votes
1
answer
42
views
REST API design with OneToMany relationship with Spring and JPA [closed]
Let's say I have two entities
public class Container {
UUID id;
String name;
@OneToMany
List<Element> elements
}
and
public class Element {
UUID id;
...
- 25
0
votes
0
answers
65
views
Cannot read the array length because "elems" is null error when running DN as jar
I've been trying so squash this bug in my program. My program runs fine with mvn test and mvn exec:java but running it as java -jar throws this error:
Exception in thread "main" java.lang....
- 35.6k
0
votes
1
answer
73
views
Spring Boot / JPA: "Unable to locate entity descriptor" after setting @OneToOne relationship to null with QueryDSL
I'm encountering a javax.persistence.PersistenceException: Unable to locate entity descriptor error in a Spring Boot application using JPA and QueryDSL.
The issue arises when I try to remove and ...
- 1,804
0
votes
0
answers
21
views
olingo-odata4-jpa-processor cannot "resolve attribute" when using $expand
So I'm trying to get into odata with JPA. I use Spring Data JPA/Hibernate, not EclipseLink. Database is local in-mem H2. I will not include my Config, to not grow the post more than necessary and I ...
- 59
0
votes
0
answers
41
views
JpaRepository delete not executing with @SQLDelete
Im using JpaRepository and performing soft-delete with @SQLDelete annotation. The database use Postgresql.
After some changes, this mechanism stopped working as intended.
Here the class that I'd like ...
- 112
0
votes
0
answers
30
views
How can I configure Hibernate to generate DDL only for entities with @Table(schema = "...")?
I'm using Spring Boot with Hibernate 6+ and PostgreSQL, and I want Hibernate to generate tables only for entities that explicitly declare a schema using @Table(schema = "schema_name").
For ...
- 435