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Hibernate throws error after migration (references on same collection)

I have a problem with using a OneToMany-Mapping with Hibernate that was working in version 4.3.8.Final but is not with version 5.4.2.Final .
When I query multiple entities from the db that have the same entries in a list that is mapped with OneToMany and then try to update those entities, hibernate throws the following exception even though I do not update any entries from the mapped relation: "Found shared reference to a collection: de.Artikel.filialeLager; nested exception is org.hibernate.HibernateException: Found shared reference to a collection: de.Artikel.filialeLager"
Here is my mapping, that was working fine with version 4.3.8.Final of Hibernate but is not anymore with 5.4.2.Final.:
#OneToMany(fetch = LAZY)
#JoinColumn(name = "SOME_ID", referencedColumnName="SOME_ID", insertable = false, updatable = false)
private List<filialeLager> filialeLager;

It seems to have a unidirectional relationship but is adding a reference column for a two-way relationship
The name of the column referenced by this foreign key column. When
used with entity relationship mappings other than the cases described
below, the referenced column is in the table of the target entity.
When used with a unidirectional OneToMany foreign key mapping, the
referenced column is in the table of the source entity. When used
inside a Join- Table annotation, the referenced key column is in the
entity table of the owning entity, or inverse entity if the join is
part of the inverse join definition. When used in a collection table
mapping, the referenced column is in the table of the entity
containing the collection.
You should have something similar to this:
#OneToMany(fetch = LAZY)
#JoinColumn(name = "SOME_ID", insertable = false, updatable = false)
private List<filialeLager> filialeLager;

Spring Boot joining two entities with invalid FK entries

I am mapping some Java classes using hibernate on a database that I have no write access for. One of the fields used as a FK between ClientEpisodes and Physician's has 6 rows that contain a -1 for the FK. THis is obviously an invalid FK, but I need to still join and simply ignore these Physicians and have a null physician.
I am joining the class using
#JoinColumn(name = "epi_phid1", referencedColumnName = "ph_id", foreignKey = #ForeignKey(ConstraintMode.NO_CONSTRAINT))
private Physician physician;
I tried specifying NO_CONSTRAINT to see if it would ignore it then, but even still I get the following error:
javax.persistence.EntityNotFoundException: Unable to find private.package.info.Physician with id -1
Is there any way to tell Hibernate to ignore values that aren't valid such as the -1?

The #ForeignKey annotation with NO_CONSTRAINT value tells hibernate to not generate foreign keys, if schema generation is used. It doesn't have any effect on the internal entity validation in the JPA framework.
There is a hibernate specific #NotFound annotation which you could use:
#JoinColumn(name = "epi_phid1", referencedColumnName = "ph_id")
#NotFound(action = NotFoundAction.IGNORE)
private Physician physician;
However be advised that if you use this in a #OneToMany or #ManyToMany annotation which maps a Collection, hibernate will fill the invalid/missing entities with null (so the list will contain null value(s)).

Apply filter on linking table in Hibernate

I've got a classic case of Category <-> Category_Product <-> Product relation.
CategoryDTO class has Set<ProductDTO> member that defined as:
#ManyToMany(cascade = CascadeType.ALL)
#JoinTable(
name = "Category_Product",
joinColumns = #JoinColumn(name = "CAT_ID"),
inverseJoinColumns = #JoinColumn(name = "PROD_ID")
)
public Set<Product> getProducts() {
return products;
}
The problem is that I want to have Category->Product relation if and only if the Category_Product.ENABLED is '1'.
I tried to use #FilterJoinTable annotation but, as I understand, it works on entities only (not on linking table), so it doesn't help here.
I hope that there is an elegant solution that uses Hibernate built-in features.

Hibernate filters documentation is clear regarding #FilterJoinTable:
When the collection use an association table as a relational
representation, you might want to apply the filter condition to the
association table itself or to the target entity table. To apply the
constraint on the target entity, use the regular #Filter annotation.
However, if you want to target the association table, use the
#FilterJoinTable annotation.
So, it should work.

Collection isn't filled with OneToMany relationship - EclipseLink

I'm mapping a database (Oracle 11g) to JPA entities using EclipseLink. I have mapped almost every table to JPA objects but I've just found a problem:
In the \Curve\ entity I have the following fields:
#Id
#Column(name = "COD_CURVE")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "seq.gen")
#SequenceGenerator(name = "seq.gen.curve", sequenceName = "SEQCURVE", allocationSize = 1)
private long codCurve;
#Id
#Column(name = "FEC_HISTORIC")
#Temporal(javax.persistence.TemporalType.DATE)
private Date fecHistoric;
#OneToMany(mappedBy="codCurve", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
private Collection<CurveDetail> detailsCollection;
In the \CurveDetail\ entity I have this:
#ManyToOne
#JoinColumns({
#JoinColumn(name = "COD_CURVE", referencedColumnName = "COD_CURVE"),
#JoinColumn(name = "FEC_HISTORIC", referencedColumnName = "FEC_HISTORIC")
})
private Curve codCurve;
The problem is that when I query the \Curve\ entity, the details always are null, despite the fact that there is valid data in both tables. Checking the database I've noticed that there are no foreign key constraints in the \CurveDetail\ table, so I wonder ¿Are these constraints required to map the database correctly? I haven't tried to add the FK constraint myself because I'm not allowed to (have to ask a DBA to do it, and it'll take a week).
Thanks in advance!

Having a foreign key is not required.
Check the SQL that is generated by enabling logging ("eclipselink.logging.level"="finest")
Try executing the same SQL with the same database to see if the data exists.
Also ensure you are not corrupting the shared cache by inserting/updating an object with a null collection. You must maintain both sides of a bi-directional relationship. You could try disabling the cache to see if this is what you are doing.

As I know having a FK constraint is not mandatory. Once I had the same problem (but it was Oracle 9i) and found out that the name of Entity class should match the name of the table you want to map, and also JPA SQL and Hibernate HQL are both case sensitive so be careful in writing #Column tag.

How can I ask Hibernate to create an index on a foreign key (JoinColumn)?

Here is my model:
class User {
#CollectionOfElements
#JoinTable(name = "user_type", joinColumns = #JoinColumn(name = "user_id"))
#Column(name = "type", nullable = false)
private List<String> types = new ArrayList<String>();
}
As you can imagine there would be a table called "user_type", which has two columns, one is "user_id" and the other is "type".
When I use hbm2ddl to generate the ddls, I want to have this table, along with the foreign key constraint on "user_id".
However, there is no index for this column. How can I get hibernate to generate the index for me?

Try an #Index annotation.
#Index(name="user_type_index")
There is also an #IndexColumn annotation used with join tables, but it doesn't seem to actually create an index, but controls which field defines order in list semantics.
The #Index column in this context does seem to create an index on the join table.

I'm dealing with a similar issue and I've found that some dialects will automatically index foreign keys and others wont.
Hibernate Dialect class and all subclasses which do not override the getAddForeignKeyConstraintString method (Oracle, SQL Server, etc) will not create an index on the foreign key.
MySQLDialect overrides that method and adds an index to every foreign key