[hibernate-issues] [JIRA] (HHH-15544) OrderColumn invalid value on add for LAZY entity

Antoine Reilles ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiMTAxMmVlNjcx... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-15544?atlOrigin=eyJpIjoiMTAxMm... ) HHH-15544 ( https://hibernate.atlassian.net/browse/HHH-15544?atlOrigin=eyJpIjoiMTAxMm... ) OrderColumn invalid value on add for LAZY entity ( https://hibernate.atlassian.net/browse/HHH-15544?atlOrigin=eyJpIjoiMTAxMm... ) Issue Type: Bug Affects Versions: 5.4.33 Assignee: Unassigned Components: hibernate-core Created: 23/Sep/2022 08:15 AM Priority: Major Reporter: Antoine Reilles ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) Hello, With two entities mapped as: @Entity @Table(name= "table_a" ) public class A { @OneToMany(fetch = FetchType.LAZY, cascade=CascadeType.ALL, mappedBy= "a" , orphanRemoval= true ) @OrderColumn(name= "rank" ) private List<B> listB = new ArrayList<>(); public void addB(B b) { listB.add(b); } } @Entity @Table(name= "table_b" ) public class B { @ManyToOne(optional = false , fetch = FetchType.LAZY) @JoinColumn(name= "blob_id" , nullable = false , insertable = true , updatable = false ) private A a; } I have an entity of type A, with no values in the list. When some code opens this entity, and directly calls “addB”, the resulting sql statements do insert a new row in table_b , but the rank value happens to be 1 if there was no direct access to the lazy listB`. If I add listB.size() before add in the addB call, then the index is valid. When I do the “add on a not yet loaded lazy list”, then the next read results in the listB containing two elements: null , then my B instance, because of the wrong rank=1 value that has been inserted. Looking at the sql traces, in the case I forget to fetch the lazy list before add, I see the calls: Hibernate: select max(rank) + 1 from table_b where a_id =? Hibernate: update table_b set rank=? where id=? When there are elements in the list, the formula max(rank)+1 results in the correct value for the added element being chosen. But when there is no element at all, the result appear to be 1 when the correct value would be 0. It looks like the formula from https://github.com/hibernate/hibernate-orm/blob/7d30b57f15617f679a20aa138... ( https://github.com/hibernate/hibernate-orm/blob/7d30b57f15617f679a20aa138... ) is too simple, and should take into account the case when there are no elements found. ( https://hibernate.atlassian.net/browse/HHH-15544#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-15544#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100207- sha1:4756b15 )