Add and drop unique key constraints are added for same key in one-to-many relationship table

[Vikas25]

I've two entities with one-to-many relationship defined as

Entity1{
// Some fields
@OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.REMOVE)
  @OrderColumn
  private List<Entity2> entity2List;
}

Entity2{
// Some fields
}

Their change sets are generated along with a relationship table but when a diffChangeLog is applied it gets generated as follows.

<changeSet author="vikas (generated)" id="123456789-10">
        <addUniqueConstraint columnNames="some_column" constraintName="UK_1" tableName="some_table"/>
    </changeSet>
<changeSet author="vikas (generated)" id="123456789-11">
        <dropUniqueConstraint constraintName="UK_1" tableName="some_table"/>
        <addUniqueConstraint columnNames="some_column" constraintName="UK_1" tableName="some_table"/>
    </changeSet>

Please note that the constraintName ("UK_1") is same in both cases. Didn't quite get the reasoning behind adding, dropping and then adding again the constraint with same name. This adds unnecessary entries in changelog file.

┆Issue is synchronized with this Jira Bug by Unito

[tsk902000]

Same issue here. It wasnt fix in 3.9.

This is use to connect to oracle 12c but it keeps regenerating the index key.
example:
https://github.com/kai902000/LiquibaseSpringboot

[rethab]

I'm seeing the same behavior for a composite primary key. When running a diff (with the gradle plugin), I get a notice that the primary key has changed:

Changed Primary Key(s): 
     usersPK on HIBERNATE.users(a_id, b_id, c_id)
          columns changed from '[HIBERNATE.users.a_id, HIBERNATE.users.b_id, HIBERNATE.users.c_id]' to '[public.users.c_id, public.users.b_id, public.users.a_id]'

I tried two things, but to no avail:

• I tried to specify the schema in the gradle plugin (as described here Pass defaultSchemaName via command line liquibase-gradle-plugin#48) suspecting that the problem was HIBERNATE vs. public. However liquibase-hibernate seems to have a hard-coded schema name: liquibase-hibernate5 V3.6 wrongly returning "HIBERNATE" as defaultCatalog and SchemaName #160
• I tried to change the order of the columns in the primary keys. I managed to do this by renaming, because they seem to be ordered alphabetically with hibernate: https://stackoverflow.com/a/25912739

---

I also noticed that when generating an initial changelog (against an empty database), this composite primary key is created by marking the columns as such:

- column:
  constraints:
    primaryKey: true
    primaryKeyName: usersPK

however the changes that are generated as a result of running ./gradlew diffChangeLog (against a database that should have all tables etc) first creates a new unique index, then drops the primary key and lastly creates a new primary key. I am not sure if this behavior of separately creating the unique index and primary key is expected though.

[rethab]

So right after writing the above comment, I tried one last thing: Update liquibase and liquibase-hibernate to 4.0.0. And this totally solves this issue 🎉

Not sure if that's a change in liquibase itself or liquibase-hibernate, but what I noticed is that when generating the initial changes (see second part of my comment above), primary keys are no longer created by simply marking the columns as such, but with a separate changeset like so (changed here: liquibase/liquibase@8412fdb):

- changeSet:
    changes:
    - addPrimaryKey:
        columnNames: a_id, b_id, c_id
        constraintName: usersPK
        tableName: users

And then this also made me realize that I was using liquibase 3.8.1 which is quite old.

[filipelautert]

Hi - we have some fixes and workarounds on this answer. Please reopen the issue if it is not fixable by using any of them.