I'm having an issue with my jpa repository doesn't return rows that I've manually inserted into the database (Oracle) via good old SQL
Insert into SYSTEM.USER (ID,CREDENTIALS,ISADMIN) values (USERSEQ.nextval,'foo',1);
My Jpa Repository
#RepositoryRestResource
public interface UserRepository extends JpaRepository<User, Long> {}
User entity
#Data
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "idgen")
#SequenceGenerator(initialValue = 1, allocationSize = 1, name = "idgen", sequenceName = "userseq")
private Long id;
#NotNull
private String credentials;
private boolean isAdmin;
}
The super weird thing is that entries that I've inserted via the REST interface works!
So if I create:
User A via REST API
User B via SQL statement
User C via REST API
The result of GET /api/users is A, C
After pulling out all my hair. I think I've narrowed it down to the Flashback feature Oracle has. As only A and C has entries in the Flashback. So Hibernate must do some magic behind the scene.
So my question is. How do I insert a row using SQL so it get a flashback entry also.
If the flashback thing isn't the problem. How do I make Hibernate return all the rows then?
while you are executing the SQL query in Oracle Sql Developer that time it is working own session. and JPA is working own session. i.e. JPA is not able to access the SQL query's records.
solution
Insert into SYSTEM.USER (ID,CREDENTIALS,ISADMIN) values (USERSEQ.nextval,'foo',1);
after that just fire the COMMIT command in Oracle Sql Developer.
it is working for me.
Related
I have 2 entities:
#Data
#Table("main_entities")
public class MainEntity {
#Id
private Long id;
private String anotherId;
#MappedCollection(idColumn = "main_entity_id")
private SecondEntity secondEntity;
}
#Data
#Table("second_entities")
public class SecondEntity {
#Id
private Long id;
private Long mainEntityId;
}
And exists the repository:
public interface MainEntityRepository extends CrudRepository<MainEntity, Long> {
#Query("SELECT * FROM main_entities WHERE another_id = :anotherId")
Optional<MainEntity> findByAnotherId(#Param("anotherId") String anotherId);
}
When I use the MainEntityRepository#findById(Long) - the SecondEntity is available, when I use the MainEntityRepository#findByAnotherId(String) - the SecondEntity is null
Update 2021.12.15:
if set the
#MappedCollection(idColumn = "main_entity_id")
private Set<SecondEntity> secondEntities;
Its allows to get the mapped collection via MainEntityRepository#findByAnotherId(String)
Spring Data JDBC loads 1:1 relationships with a single join and expects you to do the same when you specify a custom query.
In order to avoid ambiguities you have to use column aliases which prefix the columns with the property name of the 1:1 relation ship plus an _.
So your select should look like this:
SELECT M.ID, M.ANOTHER_ID, S.ID AS SECONDENTITY_ID, S.MAIN_ENTITY_ID AS SECONDENTITY_MAIN_ENTITY_ID
FROM MAIN_ENTITIES M
JOIN SECOND_ENTITIES S
ON M.ID = S.MAIN_ENTITY_ID
WHERE ANOTHER_ID = :anotherId
I created a complete example.
Side note: I recommend not to have an id on the non-aggregate-root entities, nor to have the reference back to the aggregate root in these entities. See Spring Data JDBC - How do I make Bidirectional Relationships?
so you want to fetch the second entity together with your main entity with your custom method?
I thinkt it has to do with the fetch type of your main entity. It is lazy by default and if you want to load both entitys you can try to set the fetch type to eager for the second entity field in your main entity. But be aware that this is not always the best option but rather a quick fix. See here for more information about fetch types.
You can also try using the join fetch as described in the accepted answer here to achieve your requested behaviour. I think that this would be the best solution.
I hope I got your question right if not please try to explain with further detail.
New to spring data JPA. I have sequence created in oracle table. I am using JPARepository saveall() method to save the data. Inserts work without any problem but when i try to update any existing rows in the table it always tries to insert throwing unique constraint error since i have unique index created for that table.
Entity Class
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "generator1")
#SequenceGenerator(sequenceName = "emp_seq", name = "generator1",allocationSize = 1)
#Column(name = "USER_ID")
private Long id;
Save method invocation
public void persistEmployees(List<Employee> employees) {
employeeRepo.savaAll(employees);
}
Repository class
#Repository
public interface EmployeeRepository extends JpaRepository<Employee, Long> { }
How can i tell JPA to look for existing row before inserting? Any help is much appreciated!!!
In My Humble Opinion;
Using "Exists" condition-check as "sub-query" for all constrained columns, before Update will solve this.
I have an Account entity and I'm trying to persist it using save function. My code:
#Override
public Account createAccount(String pin) {
Account account = new Account();
account.setBalance(0L);
account.setPin(pin);
return accountRepository.save(account);
}
Now my entity class has an autogenerated field called accountNumber. My entity class:
#Entity
#Table(name = "accounts")
#Data
public class Account {
#Column(name = "account_number", length = 32, insertable = false)
private String accountNumber;
private Long balance;
}
Now after calling save, the entity returned has accountNumber as null but i can see in the intellij database view that it is actually not null. All the other auto-generated fields like id etc are there in the returned entity just the accountNumber is null. Default value for accountNumber is set in the sql file :
ALTER TABLE accounts
ALTER COLUMN account_number SET DEFAULT DefaultValueSerializer(TRUE, TRUE, 12);
Here, DefaultValueSerializer is the function which is generating the account number.
I've tried other solutions available here like using saveAndFlush() etc, nothing worked in my case. What can be an issue?
As mentioned in comment Hibernate is not aware about what happens in database engine level so it does not see the value generated.
It would be wise to move generation of account number to JPA level instead of using db defaults.
I suggest you to study annotations #GeneratedValue and related stuff like #SequenceGenerator. That way the control of generating account number is in JPA level and there is no need for stuff like refreshing entity after save.
One starting point: Java - JPA - Generators - #SequenceGenerator
For non-id fields it is possible to generate value in method annotated with #PrePersist as other answer suggests but you could do the initialization already in the Accounts constructor .
Also see this answer for options.
You can create an annotated #PrePersist method inside the entity in which you set its fields to their default value.
That way jpa is going to be aware of the default.
There are other such annotation avaiable for different entity lifecycle event https://docs.jboss.org/hibernate/entitymanager/3.6/reference/en/html/listeners.html
P.s. if you decide to go this way remember to remove the insertable = false
Use
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
for your IDs. And also leave your saving to saveAndFlush so you can immediately see the changes, If any. I'd also recommend separating IDs and account numbers. They should not be the same. Try debugging your program and see where the value stops passing around.
I am trying to run a native query on a repository method so that it returns the results with some counts. It was too complicated to do with JPQL, so I opted for a native query instead.
Repository
#RepositoryRestResource(collectionResourceRel="projects", path="projects")
interface ProjectRepository extends BaseRepository<Project, Long>, ProjectRepositoryCustom {
#Query(
value="SELECT p.id, p.user_id, p.title, p.description, p.created_on, p.version,(SELECT COUNT(0) FROM projectparts WHERE project_id = p.id) AS parts,(SELECT COUNT(0) FROM requests WHERE project_id = p.id) AS requests FROM projects AS p ORDER BY ?#{#pageable}",
countQuery="SELECT COUNT(0) FROM projects",
nativeQuery=true
)
Page<Project> findAll(Pageable pageable)
}
The entity has 2 properties annotated with #Transient so that the info is not persisted to the database. All the data comes back fine except the 2 transient properties which return null for the values. When I copy the query from the console and paste it in MySQL Workbench, the results are as expected and I see the counts that I need. Anyhow, not sure if there is anything else that needs to be done in order to get this native query to work as an annotation. I hard coded a value in the sub-query SELECT 55 FROM... just to see if it was a problem with the count and it still returned as null. I ran the query in Workbench and it works fine.
I've tried changing the transient property type from Integer, Long, BigInteger, long, int... and none of that made a difference. Since I'm using Groovy, I also tried def to let Groovy infer the type and that didn't work either.
I also tried running the project from the terminal instead and it still didn't work. I've tried it on a Mac and Linux and had no luck with displaying the results of the counts.
This will not work. You could use an SQLConstructorExpression however the returned instances would be unmanaged which is a major drawback.
An better option is to create a simple DB view which holds the pieces of summary info for the Project. You can them map the Project entity to both it's table and the associated summary view using the #SecondaryTable functionality of JPA.
https://en.wikibooks.org/wiki/Java_Persistence/Tables#Example_mapping_annotations_for_an_entity_with_multiple_tables
An added benefit is that you can sort and query on the summary values as for any other property.
Updated mapping:
#Entity
#Table(name = "projects")
#SecondaryTable(name = "projects_summary_vw")
public class Project{
//use Integer rather than int to avoid issue outlined here:
//http://stackoverflow.com/a/37160701/1356423
#Column(name = "parts", table = "projects_summary_vw",
insertable="false", updateable="false")
private Integer partsCount;
#Column(name = "requests", table = "requestsCount"
insertable="false", updateable="false")
private Integer requestsCount;
//other mappings as required
}
No Custom query required:
#RepositoryRestResource(collectionResourceRel="projects",
path="projects")
interface ProjectRepository extends BaseRepository<Project, Long>,
ProjectRepositoryCustom {
}
An alternative non-JPA compliant solution may be to use some vendor specific extension rather than a view. Hibernate for example has an #Formula annotation which could be used:
https://docs.jboss.org/hibernate/orm/5.1/javadocs/org/hibernate/annotations/Formula.html
#Entity
#Table(name = "projects")
public class Project{
#Formula("my count query as native sql")
private Integer partsCount;
#Formula("my count query as native sql")
private Integer requestsCount;
//other mappings as required
}
i get this error could not get next sequence value when I try to save this Entity with Hibernate:
package beans;
import javax.persistence.*;
#Entity
#Table(schema = "EVGENY")
public class Article {
#SequenceGenerator(name="ArticleGen", sequenceName="ARTICLESEC")
#Id
#GeneratedValue(generator= "ArticleGen")
private int id;
#Column(name="title")
private String title;
#Column(name="text")
private String text;
#Column(name="postat")
private String postat;
#ManyToOne
#JoinColumn(name = "USER_ID")
private UserAcc user;
public Article(){
}
Get Set...
}
insert into article (title) values('asdfaf');
in Oracle SQL Developer this insert into article (title) values('asdfaf'); works well.
if i set id variable explicitly ( Article a = new Article();a.setId(3); )
everything is OK. I double checked the name of the sequence.
Check user permissions on the sequence. Most of the time it is grant issue
I know a lot of reasons to get this exception. Maybe you can check the questions and give me some more details about your problem:
check if the 'hibernate.dialect' is set to Oracle?
permission on sequence ok (schemata, select etc.)?
is there some trigger behind the table and throwing plsql error?
some other plsql that could break the insert?
is the transaction broken?
was there an exception (sometimes silent) somwhere before the call of create (like stale state or out of bounce) so that transaction is marked for rollback?
is there a connection is erroneous error before exception?
is the entity maybe already attached (check with contains)?
do you use spring or another framework where you can add exception resolvers or translators?
which version of oracle database do you use? 10 or 11? and are the used drivers correct?
is there a findSingle call before that does not return any value?