Flyway "Generate Migration File" produces incorrect DDL for @NaturalId

[mhagnumdw]

Describe the bug

If an attribute is annotated with @NaturalId, Hibernate automatically generates a unique constraint.

The "Generate Migration File" option in Dev UI > Extensions > Flyway reports a diff that does not exist, for example:

    alter table jarvis.DEMANDA 
       drop constraint UKm5w2uipg0ovfi452ah22gkibr;

    alter table jarvis.DEMANDA 
       add constraint UKm5w2uipg0ovfi452ah22gkibr unique (IDENTIFICADOR);

Expected behavior

No response

Actual behavior

No response

How to Reproduce?

Create an entity like this:

@Entity
@Table(name = "DEMANDA")
public class Demanda {

    @NaturalId
    @Column(name = "IDENTIFICADOR", nullable = false, updatable = false, length = 50)
    private String identificador;
}

Create the corresponding migration file.

Generate the migration file via Dev UI.

Output of uname -a or ver

Linux dwnote2 6.19.10-200.fc43.x86_64 #1 SMP PREEMPT_DYNAMIC Wed Mar 25 16:09:19 UTC 2026 x86_64 GNU/Linux

Output of java -version

openjdk version "21.0.9" 2025-10-21 LTS OpenJDK Runtime Environment Temurin-21.0.9+10 (build 21.0.9+10-LTS) OpenJDK 64-Bit Server VM Temurin-21.0.9+10 (build 21.0.9+10-LTS, mixed mode, sharing)

Quarkus version or git rev

3.31.4

Build tool (ie. output of mvnw --version or gradlew --version)

3.9.12

Additional information

No response

[quarkus-bot]

/cc @cristhiank (flyway), @gastaldi (flyway), @geoand (flyway), @gsmet (flyway)