spring data JPA deletion - spring-data

Question

I am getting a foreign key violation when I try to delete a record.
I have this record:
#Entity
public class Parent {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long parentId;
#OneToOne(cascade = CascadeType.ALL, orphanRemoval = true)
#JoinColumn(name = "childId")
private Child child;
and
#Entity
#Table(name = "Child")
public class Child {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long childId;
public Long getOperatoryId() {
return id;
}
When I try to delete the child, I get a key violation because there are some parent records that point to the children. I thought I could delete the parent first, then go delete the children as:
parentRepository.delete(parent)
but I get an error that the property id doesn't exist on child. Is this because the child id is named childId and not id?

Answer 1

Here I worked on similar example what did you asked for. Customize it based on your need.
SQL Server table create query
CREATE TABLE "DBO"."Parent"(
Parent_Id INT PRIMARY KEY NOT NULL,
Parent_Name VARCHAR(255) NOT NULL)
CREATE TABLE "DBO"."Child"(
Child_Id INT PRIMARY KEY NOT NULL,
Child_Name VARCHAR(255) NOT NULL,
Parent_Ref_Id int not null,
CONSTRAINT FK_Parent_Ref_Id FOREIGN KEY (Parent_Ref_Id) REFERENCES Parent(Parent_Id)
)
Spring data JPA code
Parent Entity
#Entity(name = "Parent")
#Table(name = "Parent")
public class Parent {
#Id
#Column(name = "Parent_Id")
private long parentId;
#Column(name = "Parent_Name")
private String parentName;
//cascade = {CascadeType.REMOVE} OR orphanRemoval = true
#OneToOne(cascade = {CascadeType.ALL},orphanRemoval = true,fetch = FetchType.LAZY,mappedBy="parentInfo")
private Child childInfo;
public long getParentId() {
return parentId;
}
public void setParentId(long parentId) {
this.parentId = parentId;
}
public String getParentName() {
return parentName;
}
public void setParentName(String parentName) {
this.parentName = parentName;
}
public Child getChildInfo() {
return childInfo;
}
public void setChildInfo(Child childInfo) {
this.childInfo = childInfo;
}
}
Child Entity
#Entity(name = "Child")
#Table(name = "Child")
public class Child {
#Id
#Column(name = "Child_Id")
private int childId;
#Column(name = "Child_Name")
private String childName;
#OneToOne
#JoinColumn(name = "Parent_Ref_Id", referencedColumnName = "Parent_Id")
private Parent parentInfo;
public int getChildId() {
return childId;
}
public void setChildId(int childId) {
this.childId = childId;
}
public String getChildName() {
return childName;
}
public void setChildName(String childName) {
this.childName = childName;
}
public Parent getParentInfo() {
return parentInfo;
}
public void setParentInfo(Parent parentInfo) {
this.parentInfo = parentInfo;
}
}
Child Repo Code
public interface ChildRepo extends CrudRepository<Child,Long> {
}
Parent Repo Code
public interface ParentRepo extends CrudRepository<Parent,Long> {
Parent findByParentId(long id);
}
Controller Code
#Autowired
private final ParentRepo parentRepo;
....
private void save() {
//Save the parent
Parent p = new Parent();
p.setParentId(1);
p.setParentName("Parent1");
Child c = new Child();
c.setChildId(1);
c.setChildName("Child1");
c.setParentInfo(p);
p.setChildInfo(c);
parentRepo.save(p);
//delete the parent and child as well
Parent p1 = parentRepo.findByParentId(1);
parentRepo.delete(p1);
}