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Hibernate version:3.1/3.2


hi, i have a simple oneToMany Association,
project -->* ChangeHistoryEntry

through hibernate-Annotation can auto. create 3 tables, project-Table, ChangeHisEntry-Table, and a project_changehistoryentries(association Table).

here is the code in project.java:

@OneToMany(targetEntity = ChangeHistoryEntry.class)
@JoinTable(
name="pro_changehistoryentries",
// joinColumns = { @JoinColumn( name="PROJECT", nullable = false) },
joinColumns = { @JoinColumn( name="PROJECT", nullable = false) },
inverseJoinColumns = @JoinColumn( name="CHANGE_HISTORY_ENTRY")
)
//or default @OneToMany
private Collection <ChangeHistoryEntry> changeHistoryEntries = new HashSet<ChangeHistoryEntry> (0); //1 -> *


public Collection getChangehistoryentrieses() {
return this.changeHistoryEntries;
}


public void setChangehistoryentrieses(Collection<ChangeHistoryEntry> changeHistoryEntries) {
this.changeHistoryEntries = changeHistoryEntries;
}

see next post

by setChangeHistoryEntries(ChangeHistoryEntrie(s))
if one of this ChangeHistoryEntrie(s) has been already set to another project and this relation has existed in that association Table pro_ChangeHistoryEntries,
if i set this ChangeHistoryEntries to a new project,
get the following failue message:
java.sql.BatchUpdateException: Duplicate entry '402880f1133e27c601133e2902200006' for key 1


the ids were all generated auto. like this:
@Id @GeneratedValue(generator="system-uuid")
@GenericGenerator(name="system-uuid", strategy = "uuid")
@Column(name = "PRO_ID")
private String id;

anybody has idea?

the problem is,

the hibernate annotation auto created a rowId(i think like TableId) changeHistoryEntries_CHA_ID and his index into the associationTable project_change_history_entry. That is why one cha_id can only be set to one project.

how can i create this associationTable without the rowId?

again the code:

@Entity
@Table(name="project")

public class Project implements java.io.Serializable {

// Fields

@Id @GeneratedValue(generator="system-uuid")
@GenericGenerator(name="system-uuid", strategy = "uuid")
@Column(name = "PRO_ID")
private String id;

....
@OneToMany(cascade={CascadeType.ALL})
private Collection <ChangeHistoryEntry> changeHistoryEntries = new HashSet<ChangeHistoryEntry> (0); //1 -> *

....

}

@Entity
@Table(name="change_history_entry")

public class ChangeHistoryEntry implements java.io.Serializable {

// Fields

@Id @GeneratedValue(generator="system-uuid")
@GenericGenerator(name="system-uuid", strategy = "uuid")
@Column(name = "CHA_ID")
private String id;
....}

Hi,

Try annotating your Collection with @CollectionId to force the creation of a separate column to store the primary key.

Cheers,

Andy

sorry, my question is false.

this is a 1->* relationship. Of course, each Object from *.side can only belong to 1 Object from 1.side.

sorry