I have a class A having id,name and list of some integers which are ordered.Class A is mapped to Table A and the list of value type in this case integers are mapped to table B.When I want to delete class A the user passes id of some object of A, the row for this id should be deleted as well as its associated children.But I dont want to use load and then delete,instead I want to know if I can delete using HQL query.I tried this but I ended up with the following error

org.springframework.dao.DataIntegrityViolationException: Hibernate operation: could not execute update query; SQL [delete from A where ID=?]; Integrity constraint violation FKCC295055F9F89D2D table: B in statement [delete from A where ID=?];

First of all,how would the mapping look like?
Is there a way out for the above problem?

this basically depends on your db design.

table B should have a foreign key to A - basically FKCC295055F9F89D2D
if you have mapped A-->B as one-to-many

if you are sure that A-->B is a "contained" relationship i.e. if A is deleted you want to delete B add on-delete="cascade" on the one-to-many relation OR just alter the constraint in the DB directly.

any way you do it, now if you delete A with HQL all the B's will go away without having to load them into memory

I have the following class with hibernate annotation

@Entity
@Table(name = "A")
@Proxy(lazy = false)
public class A {
private Integer id;
private List<Integer> masterIds;

@Id @GeneratedValue(generator = "uuid-generator")
@Column(name = "A_ID", nullable = false)
public Integer getId() {
return id;
}

@OneToMany(cascade=CascadeType.ALL)
@JoinTable(
name = "B",
joinColumns = @JoinColumn(name="A_ID"),
inverseJoinColumns = @JoinColumn(name="B_ID")
)
@IndexColumn(name="INDEX")
public List<Integer> getMasterIds() {
return null; //assume we return a ArrayList here
}
}

If I try to fire following HQL query to delete using the id I get the
"delete from "+A.class.getName()+ " a " +" where a.id = "+id;

I get the exception mentioned in my first post.
Can you tell me what I am doing wrong in the above mapping

same as what i said in my post. i'm not using annotations yet so it might looks like this:

I tried the same also, with @OnDelete(action=OnDeleteAction.CASCADE)

but it didnt work gave me the DataIIntegrityViolationException.

Did u check the query that I use, I thought with the above mapping/annotations hibernate would take care of deletion of children, if i fire that query.But :(

If I check the sql queries before delete an update query is fired I dont understand why...could it be cos of that?

I read somewhere that HQL delete cascade is not possible and the hibernate guys are working on it...Is this true? So what I am trying to achieve isnt possible for now?

the cascade deletes work fine if they are defined correctly at the db level. i use them qutie a bit myself. instead of xdoclet i directly add cascade constraints in the database

based on your db just add a constraint that looks something like



check the manual for the correct syntax. this is how you can efficiently do bulk deletes

Can you send me a sample program if you have one...