In the code below, when I call the method EntityADAO.findByGroupId(...), the table EntityA is locked until the transaction is complete. I don't want this. How can I avoid the table locking? Thanks in advance.
My database is SQL SERVER 2012. I am suing Hibernate 4.0.2.
Below is the code excerpt:
#Entity
#Table(name = EntityA)
#NamedQueries ({
#NamedQuery(name="EntityA.findByGroupId", query="SELECT p FROM EntityA p WHERE p.groupId= :groupId")})
public class EntityA implements Serializable {
#Id
#Column(name = "EntityKey", nullable = false)
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long entityKey;
#Version
#Column(name = "Version", nullable = false)
private Long version = -1l;
#NotNull
#Column(name = "GroupId")
private Integer groupId;
}
#Repository("EntityA")
#Scope(BeanDefinition.SCOPE_PROTOTYPE)
public class EntityADAO extends AbstractJpaDAO<EntityA> {
#PersistenceContext
protected EntityManager em;
public EntityADAO() {
setClazz(EntityADAO.class);
}
**//A call to this method locks the table EntityA until the transaction is complete**
public List<EntityA> findByGroupId(int groupId) {
TypedQuery<EntityA> query = em.createNamedQuery("EntityA.findByGroupId", EntityA.class);
query.setParameter("groupId", groupId);
return query.getResultList();
}
}
If I'm not wrong SQL Server does not come with row versioning enabled by default, hence I think this is why you're seeing this behavior.
What I suspect is when you issue a select query, and before this query finishes you issue another update query, the update has to wait until the select is complete.
There are many approach to solve this problem, with one being enabling the row versioning. Other option include using the least restrictive isolation level.
Related
I have an entity class and repository. Here I'm trying to execute update query but not working.
How to update Lob column in native query or any another solution on jpa query to update Lob column.
#Entity
#Table(name = "comment")
public class Comment implements Serializable {
#Basic
#Lob
#Column(name="Article_COMMENT", columnDefinition="TEXT")
private String articleComment;
#Basic
#Column(name = "ID_ARTICLE")
private Long articleId;
}
#Repository
public interface commentRepository extends JpaRepository<Comment, Long> {
#Query(value = "UPDATE comment set articleComment=: articleComment WHERE articleId =: articleId", nativeQuery=true)
void updateComment(#Param("articleComment") String articleComment, #Param("articleId") Long articleId );
}
Error:
No results were returned by query.
JpaSystemException thrown with message: could not extract ResultSet; nested exception is org.hibernate.exception.GenericJDBCException: could not extract ResultSet
Your question is very vague so I can answer on assumptions only. I think You want to update the articalComment field of your Entity. You can simply use .save() method of JpaRepository. Your code should be as follows. Here I am also assuming that your articleId is unique identifier to your entity class.
#Entity
#Table(name = "comment")
public class Comment implements Serializable {
#Basic
#Lob
#Column(name="Article_COMMENT", columnDefinition="TEXT")
private String articleComment;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "ID_ARTICLE")
private Long articleId;
}
Now your Id should be unique and has a #Id Annotation to identify it inside spring data JPA.
You don't have to add any code inside of your JPA repository. Simply call commentRepository.save(commentObject) method. If commentObject has an ID as 0 then a new Comment will be created. If the ID is a positive value and is present in your table that particular row will be updated not created.
remove the space try this way
UPDATE comment set articleComment=:articleComment WHERE articleId =:articleId
I'm using #UniqueConstraint in the below code.when im using saveall()
method to save the data,when constraint violation fails for the first
data remaining values are also not saving.
#Entity
#Data
#Table(uniqueConstraints = #UniqueConstraint(columnNames = { "tradeStartTime", "tradeEndTime", "contract" }))
public class TradingHours {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
private ZonedDateTime tradeStartTime;
private ZonedDateTime tradeEndTime;
#ManyToOne
#JoinColumn(name = "contract")
private Contract contract;
}
I think there is no way to continue bulk insert after transaction fail. If you need to save all remaining values, you should save each value separately in save() method marked as #Transactional(propagation = Propagation.REQUIRES_NEW), take a look at docs.
You also have to catch DataIntegrityViolationException somewhere until it breaks somthenig else.
I have created two entities Book and Book_Category with one-to-many relationship. When I issued BookCategoryRepository.findAll(), I expected hibernate to use 'INNER JOIN' query. But it just issued query to take data from Book_Category.
What I am missing? What should I do to make hibernate issue JOIN query?
Book.java
#Entity
public class Book {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int id;
private String name;
#ManyToOne
#JoinColumn(name = "book_category_id")
private BookCategory bookCategory;
}
BookCategory.java
#Entity
#Table(name = "book_category")
public class BookCategory {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int id;
private String name;
#OneToMany(mappedBy = "bookCategory", fetch = FetchType.EAGER, cascade = CascadeType.ALL)
private Set<Book> books;
}
BookCategoryRepository.java
public interface BookCategoryRepository extends JpaRepository<BookCategory, Integer> {
}
bookCategoryRepository.findAll()
Hibernate uses by default a second query to retriev the child collection. One reason for this is a proper limit query. Otherwise, there would be more rows in the result set, than entities for the 1 side, if at least one has more than 1 child.
There exists an annotation to change this behaviour in hibernate which is ignored by the Spring Data Jpa Repositories. The annotation is #Fetch(FetchMode.JOIN). You might consider How does the FetchMode work in Spring Data JPA if you really need this behaviour.
I'm getting an error
Caused by: javax.persistence.EntityNotFoundException: Unable to find tn.entities.AgenceBnq with id 01
when I get AgenceBnq through Employee
Employee class:
#Table(name = "EMPLOYEE")
#NamedQuery(name = "Employee.findById", query = "SELECT e FROM Employee e WHERE e.employeMat = ?1"),
public class Employee implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(name = "EMPLOYEE_MAT", unique = true, nullable = false, length = 15)
private String employeeMat;
...
#ManyToOne
#JoinColumn(name = "AGENCE_COD")
private AgenceBnq agenceBnq;
}
#Entity
#Table(name="AGENCEBNQ")
public class AgenceBnq implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(name="AGENCE_COD", unique=true, nullable=false, length=10)
private String agenceCod;
...
//bi-directional many-to-one association to Employee
#OneToMany(mappedBy="agenceBnq")
private Set<Employee> employees;
}
I'm calling namedQuery Employee.findById in DAO to retrieve data and I have to get AgenceBnq from Employee but get this error while calling query.getResultList()
#NotFound( action = NotFoundAction.IGNORE) isn't useful for me because data exist in AGENCEBNQ table and I have to retrieve date through Employee.
Is this a bug in hibernate ? I'm using hibernate version 3.6.7.Final
Firstly, You dont need query for it, the EnityManger.find(Employee.class, YOUR_ID) will do the job.
Secondly dont use ? in your queries but names (e.employeMat = :id) as it is easier to debug and less error prones for complicated queries.
Finally, check your DB table if the AGENCE_COD column in Employee table really contains the valid ID for your entitity that crashes (and that it length matches the ID length of AgenceBnq). It should work, the typical reason why it doesnt will be that your Employe.AGENCE_COD has defualt value and when creatubg the new EMploye you add it only to the Agence but you did not set Agence in the Employ.
Hi I am new to Spring Data JPA and I am wondering even though I pass the Id to the entity, the Spring data jpa is inserting instead of merge. I thought when I implement the Persistable interface and implement the two methods:
public Long getId();
public Boolean isNew();
It will automatically merge instead of persist.
I have an entity class called User like:
#Entity
#Table(name = "T_USER")
public class User implements Serializable, Persistable<Long> {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "USER_ID")
private Long id;
#Column(name = "CREATION_TIME", nullable = false)
private Date creationTime;
#Column(name = "FIRST_NAME", nullable = false)
private String firstName;
#Column(name = "LAST_NAME", nullable = false)
private String lastName;
#Column(name = "MODIFICATION_TIME", nullable = false)
private Date modificationTime;
And have another class
#Entity
#Table(name = "T_USER_ROLE")
public class UserRole implements Serializable, Persistable<Long> {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long roleId;
#Column(name = "ROLE_NAME")
private String userRole;
}
I have a custom repository called UserRepostory extending JpaReopistory. I am hitting the save for merge and persist as I see the implementation demonstrate that Spring Data Jpa uses above two methods to either update or insert.
#Repository
public interface UserRepository extends JpaRepository<User, Long> {
}
I have been trying to figure out but didn't get any clue. Maybe you
guys can help.
I ran into this issue, tried to implement Persistable to no avail, and then looked into the Spring Data JPA source. I don't necessarily see this in your example code, but I have a #Version field in my entity. If there is a #Version field Spring Data will test that value to determine if the entity is new or not. If the #Version field is not a primitive and is null then the entity is considered new.
This threw me for a long time in my tests because I was not setting the version field in my representation but only on the persisted entity. I also don't see this documented in the otherwise helpful Spring Data docs (which is another issue...).
Hope that helps someone!
By default Spring Data JPA inspects the identifier property of the given entity. If the identifier property is null, then the entity will be assumed as new, otherwise as not new. It's Id-Property inspection Reference
If you are using Spring JPA with EntityManager calling .merge() will update your entity and .persist() will insert.
#PersistenceContext
private EntityManager em;
#Override
#Transactional
public User save(User user) {
if (user.getId() == null) {
em.persist(user);
return user;
} else {
return em.merge(user);
}
}
There is no need to implement the Persistable interface.