Benedikt Waldvogel ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiOTkwNGM4NmNj... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16943?atlOrigin=eyJpIjoiOTkwNG... ) HHH-16943 ( https://hibernate.atlassian.net/browse/HHH-16943?atlOrigin=eyJpIjoiOTkwNG... ) Column ordering leads to wrong column order in unique constraints ( https://hibernate.atlassian.net/browse/HHH-16943?atlOrigin=eyJpIjoiOTkwNG... ) Issue Type: Bug Affects Versions: 6.2.6 Assignee: Unassigned Components: hibernate-core Created: 17/Jul/2023 01:14 AM Priority: Major Reporter: Benedikt Waldvogel ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) Given ----- @Entity @Table(uniqueConstraints = @UniqueConstraint(name = "uk_b_a" , columnNames = { "b" , "a" })) class TestEntity { @Id private Long id; private String b; private String a; } Note that we define an explicit unique constraint on the columns *(b, a)* (in that very order). The column order could be important since the underlying unique index should be used to speed-up queries that select all entities for a given value of “b”. Actual vs. Expected ------------------- When the schema gets created in the context of a JPA EntityManagerFactory, the columns are (re-)ordered during construction of the SessionFactoryImpl, Line 252: bootMetamodel.orderColumns( false ) ( https://github.com/hibernate/hibernate-orm/blob/58aff00957721074a4a393725... ) This leads to the following DDL: create table "TestEntity" ( id bigint not null , a varchar (255), b varchar (255), primary key (id), constraint uk_b_a unique ( a , b) ); Note that “uk_b_a” is created with columns *(a, b)* instead of the expected column order *(b, a)*. Workaround ---------- One can restore the behavior of Hibernate 6.1 by switching to the legacy column ordering strategy via hibernate.column_ordering_strategy=legacy. Test Case --------- Upcoming: I’ll submit a PR with a unit test for this issue. ( https://hibernate.atlassian.net/browse/HHH-16943#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16943#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#100232- sha1:33a7c72 )