I have two classes: Category and Event. And i have a Many-To-Many relationship between then that created a table "events-categories". When i try to delete a category that is related with some event i get this error message
"could not execute statement; SQL [n/a]; constraint ["FK646NVTVT2IKHQCVFM14QKNF62: PUBLIC.EVENTS_CATEGORY FOREIGN KEY(CATEGORY_ID) REFERENCES PUBLIC.CATEGORY(ID) (CAST(2 AS BIGINT))"; SQL statement:\ndelete from category where id=? [23503-212]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement"
What i want is to delete a category and no delete the events that have this category. I just want to set the deleted category in the events to null
Thats the code of the Entitys
#Data
#Entity
public class Category {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Column(length = 20, nullable = false)
private String name;
#ManyToMany
private Set<Event> events;
}
#Data
#Entity
public class Event {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Column(length = 80, nullable = false)
private String description;
#Column(nullable = true)
private LocalDate[] eventDate;
#ManyToMany
#JoinTable(name = "events_categories", joinColumns = #JoinColumn(name = "event_id"), inverseJoinColumns = #JoinColumn(name = "category_id"))
private Set<Category> categories;
}
Related
There is a table ORDERS from which were created views ORDER_VIEW_A and ORDER_VIEW_B.
I have created entity classes OrderViewA and OrderViewB where in each of them is mapping on entity named 'TransactionRecord'.
It is #OneToOne relationship.
There is column ORDER_ID in TRANSACTION_RECORD table and field orderId in TransactionRecord entity.
Field orderId is same for OrderViewA.id and for OrderViewB.id, cause views are selected from the same table.
My question is, how to map in Hibernate two views in OneToOne relationship with another entity by same field.
My code looks like this and it doesn't work in any way, Hibernate always end up with:
org.hibernate.AnnotationException: Referenced property not a
(One|Many)ToOne: com.example.app.model.TransactionRecord.orderId in
mappedBy of com.example.app.model.views.OrderViewA.orderViewA
#Entity
#Immutable
#Table(name = "ORDER_VIEW_A")
public class OrderViewA {
#Id
#Column(name = "id")
private Long id;
...
#OneToOne(mappedBy = "orderId", fetch = FetchType.LAZY)
private IntegrationRecord orderARecord;
...
}
#Entity
#Immutable
#Table(name = "ORDER_VIEW_B")
public class OrderViewB {
#Id
#Column(name = "id")
private Long id;
...
#OneToOne(mappedBy = "orderId", fetch = FetchType.LAZY)
private IntegrationRecord orderBRecord;
...
}
#Entity
#Table(name = "TRANSACTION_RECORD")
public class TransactionRecord {
#Id
#Column(name = "id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "order_id")
private Long orderId;
...
#OneToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "order_id")
private OrderViewA orderViewA;
#OneToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "order_id")
private OrderViewB orderViewB;
...
}
While writing my application I came across a problem with executting SQL statement. I tried to look for a solution on the net, but none of the found helped and I still do not know how to deal with an error I get. Here is exception I get:
org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint ["FKAM8LLDERP40MVBBWCEQPU6L2S: PUBLIC.BOOK_CATEGORY FOREIGN KEY(CATEGORY_ID) REFERENCES PUBLIC.CATEGORY(ID) (2)"; SQL statement:
insert into book_category (book_id, category_id) values (?, ?) [23506-196]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement
And this is how the classes looks:
Book.class
#Entity
#Table(name = "book")
public class Book {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(nullable = false)
private String title;
private String description;
#Column(name = "release_date")
#Temporal(TemporalType.TIMESTAMP)
private Date releaseDate;
#JoinColumn(name = "cover_image")
#OneToOne(cascade = CascadeType.MERGE)
private UploadFile coverImage;
#OneToOne(cascade = CascadeType.MERGE)
private UploadFile content;
#ManyToMany
#JoinTable(name = "book_category", joinColumns = {#JoinColumn(name = "book_id", referencedColumnName = "id")},
inverseJoinColumns = {#JoinColumn(name = "category_id", referencedColumnName = "id")})
private Set<Category> categories;
// constructors, setters, getters
}
Category.class
#Entity
#Table(name = "category")
public class Category {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "category_name")
private String name;
#ManyToMany(mappedBy = "categories", fetch = FetchType.LAZY)
private List<Book> books;
// ...
}
Your are missing cascade definitions there.
Your Book Category gets written before a referenced entity (book or category) gets inserted first. This is not allowed due to the constraint you specified. The solution is to define
cascade = CascadeType.ALL
On both sides of the join (both in books and in categories). This is going to ensure that JPA persists all entities in the right order.
I have two classes that have 2 relations between them.
User class:
#Entity
#Table(name="User")
public class User implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="Id")
private long id;
#OneToMany(cascade = CascadeType.ALL, fetch=FetchType.EAGER, mappedBy="admin")
private Set<Group> ownedGroup;
#ManyToMany(cascade = CascadeType.ALL, fetch=FetchType.EAGER, mappedBy="members")
private Set<Group> memberGroups;
//.......
}
Group class:
#Entity
#Table(name="Group")
public class Group implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="Id")
private long id;
#NotNull
#ManyToOne(cascade=CascadeType.ALL, fetch=FetchType.EAGER)
#JoinColumn(name="Admin", referencedColumnName="Id")
private User admin;
#ManyToMany(cascade=CascadeType.ALL, fetch=FetchType.EAGER)
#JoinTable(name = "Group_User",
joinColumns = #JoinColumn(name = "Group"),
inverseJoinColumns = #JoinColumn(name = "User"))
private Set<User> members;
//....
}
When I want to start the App, I get this exception:
org.hibernate.AnnotationException: Use of #OneToMany or #ManyToMany targeting an unmapped class: com.myproject.model.User.memberGroups[com.querydsl.core.group.Group]
I saw other similar posts, but apparently they didn't use javax.persistence.Entity and it was the root cause of this error. Any idea how to resolve this issue ?
Group is a reserved keyword. Use backtick to escape a reserved keyword. Check out this answer.
#Table(name = "`Group`")
Also your #ManyToMany mapping is unfortunately not correct.
Update your Group entity like so :
#Entity
#Table(name="`Group`") // Change your table name
public class Group implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="Id")
private long id;
#NotNull
#ManyToOne(cascade=CascadeType.ALL, fetch=FetchType.EAGER)
#JoinColumn(name="Admin", referencedColumnName="Id")
private User admin;
#ManyToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
#JoinTable(
name = "Group_User",
joinColumns = #JoinColumn(name = "group_id", referencedColumnName = "id"), //Give a column name 'group_id' and map it to Group primary key id
inverseJoinColumns = #JoinColumn(name = "user_id", referencedColumnName = "id") //Give a column name 'user_id' and map it to User primary key id.
)
private Set<User> members;
...
}
I use hibernate and spring-data. There are two tables with many-to-many relationship.
#Entity
#Table(name = "FirstEntity")
public class FirstEntity {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "first_entity_id")
private Long id;
#Column(name = "first_entiry_name")
private String name;
/* getters and setters are below*/
}
#Entity
#Table(name = "SecondEntity")
public class SecondEntity {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "second_entity_id")
private Long id;
#Column(name = "second_entiry_name")
private String name;
#Column(name = "second_entiry_desc")
private String description;
/* getters and setters are below*/
}
And entity for cross-reference table.
#Entity
#Table(name = "FirstSecondEntity")
public class FirstSecondEntity {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "first_second_entity_id")
private Long id;
#Column(name = "first_entity_id")
private Long firstEntityId;
#Column(name = "second_entity_id")
private Long secondEntityId;
/* getters and setters are below*/
}
I need SELECT like this
SELECT FirstEntity.name, SecondEntity.name, SecondEntity.description FROM SecondEntity INNER JOIN FirstSecondEntity ON SecondEntity.id = FirstSecondEntity.secondEntityId INNER JOIN User ON FirstEntity.id = FirstSecondEntity.firstEntityId
i.e. I need all records from cross-reference table where instead of ids there is actual info from entities.
Inserting this query into #Query annotation in my CrudRepository-extended class doesn't work because of
ERROR [main][org.hibernate.hql.internal.ast.ErrorCounter] Path expected for join!
So I need your help.
Your join table is all screwed up. In this case, you actually don't even need the join table as a hibernate mapping:
In Second Entity add the following list:
#ManyToMany(fetch = FetchType.LAZY)
#JoinTable(name = "FirstSecondEntity",
joinColumns = {
#JoinColumn(name = "first_entity_id",
nullable = false,
updatable = false) },
inverseJoinColumns = {
#JoinColumn(name = "second_entity_id",
nullable = false,
updatable = false) },
)
private List<FirstEntity> firstEntities;
In FirstEntity add the following list:
#ManyToMany(fetch = FetchType.LAZY,
mappedBy = "firstEntities")
private List<SecondEntity> secondEntities;
I have three entities. The first one is Company entity (see below).
#Entity
public class Company {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
#Column
private String name;
#JoinColumn(name = "company_id")
#OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
private List<Employee> employees;
#OneToMany(mappedBy = "company")
private List<HistoryRecord> historyRecords;
The second is Employee
#Entity
public class Employee {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
Integer id;
#Column
String name;
#ManyToOne
#JoinColumn(name = "company_id", nullable = true)
private Company company;
#OneToMany(mappedBy = "employee")
private List<HistoryRecord> historyRecords;
Here is my HistoryRecord class
#Entity
public class HistoryRecord {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
Integer id;
#ManyToOne
#JoinColumn(name = "company_id")
Employee employee;
#ManyToOne
#JoinColumn(name = "employee_id")
Company company;
#Column(name = "hire_date")
Date hireDate;
#Column(name = "resign_date")
Date resignDate;
When I'm trying to execute delete operation on Employee I'm getting this error
HTTP Status 500 - Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: Could not execute JDBC batch update; SQL [delete from employee where id=?]; constraint ["CONSTRAINT_12: PUBLIC.HISTORY_RECORD FOREIGN KEY(EMPLOYEE_ID) REFERENCES PUBLIC.EMPLOYEE(ID)
I think the problem is in cascade operation but I'm not sure. Is anybody can say how can I fix it?
The problem is due to the relationship of Employee -- HistoryRecord. The employee property on HistoryRecord is not nullable. If you want the HistoryRecord to be deleted when an employee is being deleted you need to add the cascade attribute to the #OneToMany(mappedBy = "employee") for historyRecords on Employee.
#OneToMany(mappedBy = "employee",cascade = CascadeType.REMOVE)
The ENDDM generates
ALTER TABLE "public"."project_group" ADD CONSTRAINT "mandant" FOREIGN KEY (mandant_id) REFERENCES "mandant" ("mandant_id") ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED;
for the database and
#OneToMany(cascade = CascadeType.REMOVE)
in Java.
Update your relation mapping in Company class is is missing cascade.
#OneToMany(mappedBy = "company", cascade = CascadeType.ALL)
private List<HistoryRecord> historyRecords;