@OneToOne - too many joins -------------------------- Key: HHH-5109 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-5109 Project: Hibernate Core Issue Type: Bug Components: annotations, core Affects Versions: 3.5.0-Final Reporter: Marek Romanowski Attachments: hibernate-one-to-one.zip With classes like this: @Entity @Proxy(lazy=false) class Owner { @javax.persistence.Id @javax.persistence.Column(name = "ID", columnDefinition = "BIGINT") public java.lang.Long getId() { return this.id; } public void setId(java.lang.Long newValue) { this.id = newValue; } private java.lang.Long id; @javax.persistence.OneToOne(targetEntity = Owned.class) @org.hibernate.annotations.Cascade( { org.hibernate.annotations.CascadeType.ALL }) @javax.persistence.PrimaryKeyJoinColumn public Owned getOwned() { return this.owned; } public void setOwned(Owned owned) { this.owned = owned; if (owned != null) { owned.setOwner(this); } } private Owned owned; } @Entity @Proxy(lazy=false) class Owned { private java.lang.Long id; @javax.persistence.Id @javax.persistence.GeneratedValue(generator = "foreign") @org.hibernate.annotations.GenericGenerator( name = "foreign", strategy = "foreign", parameters = { @org.hibernate.annotations.Parameter(name = "property", value = "owner") }) @javax.persistence.Column(name = "ID", columnDefinition = "BIGINT") public java.lang.Long getId() { return this.id; } public void setId(java.lang.Long newValue) { this.id = newValue; } @javax.persistence.OneToOne(targetEntity = Owner.class, mappedBy = "owned") @javax.persistence.PrimaryKeyJoinColumn public Owner getOwner() { return this.owner; } public void setOwner(Owner owner) { this.owner = owner; } private Owner owner; } Idea is to have one to one relation between Owner and Owned mapped by "id" properties in both entities. So for each pair owner.id == owned.id. code: session.load(Owner.class, 1L) turns into SQL: select owner0_.ID as ID0_2_, owned1_.ID as ID1_0_, owner2_.ID as ID0_1_ from Owner owner0_ left outer join Owned owned1_ on owner0_.ID=owned1_.ID left outer join Owner owner2_ on owned1_.ID=owner2_.ID where owner0_.ID=? Isn't it wrong? @OneToOne annotation on getOwner() has mappedBy="owned" property, so I would expect this code to generate SQL with only one join (only "owner join owned"). If this is correct H3 behaviour in this case, then write what should I change in annotations to get described behaviour, please. I've attached maven project with one test encapsulating this issue. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://opensource.atlassian.com/projects/hibernate/secure/Administrators.... - For more information on JIRA, see: http://www.atlassian.com/software/jira