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How to ignore updatable = false annotation?

If a field is annotated updatable=false, the column will not be included in SQL UPDATE.
This is desired default behavior. But in one specific flow, I need to update this this column. Is there a way to ignore this annotation? Or do I need to DELETE and INSERT entry?
#Column(name = "client_rating", updatable = false)
private Integer clientRating;

Hibernate - Map the same column to two diferent variables

I am trying to map the same column to two diferent variables, like the following code:
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name="Class", insertable = false, updatable = false)
#Fetch(FetchMode.JOIN)
private ObjectClass classObject;
#Column(name="Class")
private int classID;
But when i try to get the classObject i get a null and the classID is with the right value. For some reason the classObject is not getting fetched....
Can you guys help???

How to control hibernate reverse engineering #JoinTable and it's elements?

I am using hibernate Reverse Engineering tool to generate pojo's from my database. Say I have two table's A and B in my database and another table ABMap which has two columns A_id and B_id that are foreign keys to table A and B respectively, and the primary key of ABMap is the composite key of A_id and B_id.
Now, when I build my project and generate the pojos, instead of ABMap being generated as a separate entity by hibernate, it is added into the entity A as a Set. Below is the snippet of code generated in entity A,
#ManyToMany(fetch = FetchType.LAZY)
#JoinTable(name = “ABMap”, schema= “myDB”, joinColumns = {
#JoinColumn(name = “A_id”, nullable = false, updatable = false) }, inverseJoinColumns = {
#JoinColumn(name = “B_id”, nullable = false, updatable = false) })
public Set getBs() {
return this.bs;
}
public void setBs(Set bs) {
this.bs = bs;
}
Now the issue here is, using hibernate or Jpa I can do a insert into the ABMap table without actually having an entity of ABMap but I cannot update the same record since the updatable element in #JoinColumn is set to false by hibernate reverse engineering tool. Below is the sql error that occurs when an attempt is made to update the value of B_id.
2014-12-17 13:26:50,639 ERROR (qtp850520326-20) [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] - The UPDATE statement conflicted with the FOREIGN KEY constraint "FK_A_B". The conflict occurred in database "myDB", table "B", column 'B_id'.
How can I set the updatable element in #JoinColumn to true?

#OrderColumn generates a request to update the primary key

I use a list. The list is comprised of a compound primary key which is also used for sorting the list.
The problem is that if I delete an element in the list (key compound),
annotation #OrderColumn generates a request to update a primary key, and the cost rises an exception of type:
[26-05-2011 10:34:18:835] WARN org.hibernate.util.JDBCExceptionReporter - SQL Error: 1062, SQLState: 23000
[26-05-2011 10:34:18:835] ERROR org.hibernate.util.JDBCExceptionReporter -Duplicate entry '10-10' for key 'PRIMARY'
[26-05-2011 10:34:18:835] ERROR org.hibernate.event.def.AbstractFlushingEventListener - Could not synchronize database state with session org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
Here is the definition of the mapping :
#ManyToMany(cascade=CascadeType.ALL, fetch = FetchType.LAZY)
#JoinTable(name = "chapter_item", joinColumns = { #JoinColumn(name = "chapter_id", nullable = false, updatable = false) }, inverseJoinColumns = { #JoinColumn(name = "item_id", nullable = false, updatable = false) })
#OrderColumn(name="iorder")
public List<Item> getItems() {
return items;
}
Here is the update query where I have a problem:
Hibernate:
update
chapter_item
set
item_id=?
where
chapter_id=?
and iorder=?
I wonder if this is a known bug, and if anyone has a solution?

Regarding #OrderColumn, following documentation is found at http://docs.oracle.com/javaee/6/api/javax/persistence/OrderColumn.html
Specifies a column that is used to maintain the persistent order of a
list. The persistence provider is responsible for maintaining the
order upon retrieval and in the database. The persistence provider is
responsible for updating the ordering upon flushing to the database to
reflect any insertion, deletion, or reordering affecting the list.
So we see that the persistence provider i.e. hibernate is responsible for updating the column named iorder. It is also said that:
The OrderColumn annotation is specified on a OneToMany or ManyToMany
relationship or on an element collection. The OrderColumn annotation
is specified on the side of the relationship that references the
collection that is to be ordered. The order column is not visible as
part of the state of the entity or embeddable class.
Please take note of the sentence that says:
The order column is not visible as part of the state of the entity or
embeddable class.
So, may I suggest you to consider not selecting the column iorder for #OrderColumn since it is a part of your composite key and hibernate is sure to update this value when you delete or insert an element in list (List<Item>).
Hope, this helps.

Maybe one option could be change the order annotation and use:
#ManyToMany(cascade=CascadeType.ALL, fetch = FetchType.LAZY)
#JoinTable(name = "chapter_item", joinColumns = { #JoinColumn(name = "chapter_id", nullable = false, updatable = false) }, inverseJoinColumns = {#JoinColumn(name = "item_id", nullable = false, updatable = false) })
#org.hibernate.annotations.Sort(type = SortType.COMPARATOR, comparator = ItemComparator)
public List<Item> getItems() {
return items;
}
https://dzone.com/articles/sorting-collections-hibernate
Check performance solution because maybe is too slow for big amount of data, and if you can share if was a possible solution would be great to know

Hibernate: Where do insertable = false, updatable = false belong in composite primary key constellations involving foreign keys?

When implementing composite primary keys in Hibernate or other ORMs there are up to three places where to put the insertable = false, updatable = false in composite primary key constellations that use identifying relationships (FKs that are part of the PK):
Into the composite PK class' #Column annotation (#Embeddable classes only) or
Into the entity class' association #JoinColumn/s annotation or
Into the entity class' redundant PK property's #Column annotation (#IdClass classes only)
The third is the only way to do with #IdClass and JPA 1.0 AFAIK. See http://en.wikibooks.org/wiki/Java_Persistence/Identity_and_Sequencing#Primary_Keys_through_OneToOne_Relationships. I will consider only cases 1. and 2.
Q:
Which way is the preferred place to put the "insertable = false, updatable = false" to generally?
I have experienced problems with Hibernate concerning this question. For example, Hibernate 3.5.x will complain about the Zips table
CREATE TABLE Zips
(
country_code CHAR(2),
code VARCHAR(10),
PRIMARY KEY (country_code, code),
FOREIGN KEY (country_code) REFERENCES Countries (iso_code)
)
with:
org.hibernate.MappingException: Repeated column in mapping for entity: com.kawoolutions.bbstats.model.Zip column: country_code (should be mapped with insert="false" update="false")
org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:676)
org.hibernate.mapping.PersistentClass.checkPropertyColumnDuplication(PersistentClass.java:698)
...
As you can see the country_code column is both PK and FK. Here are its classes:
Entity class:
#Entity
#Table(name = "Zips")
public class Zip implements Serializable
{
#EmbeddedId
private ZipId id;
#ManyToOne
#JoinColumn(name = "country_code", referencedColumnName = "iso_code")
private Country country = null;
...
}
Composite PK class:
#Embeddable
public class ZipId implements Serializable
{
#Column(name = "country_code", insertable = false, updatable = false)
private String countryCode;
#Column(name = "code")
private String code;
...
}
When putting the insertable = false, updatable = false into the entity class association's #JoinColumn all exceptions disappear and everything work fine. However, I don't see why the above code should not be working. It might be Hibernate having problems with this. Is the described a Hibernate bug, as it doesn't seem to evaluate #Column "insertable = false, updatable = false"?
In essence, what's the standard JPA way, the best practice, or preference where to put "insertable = false, updatable = false"?

Let me answer step by step.
1. When do you need ` insertable = false, updatable = false`?
Let's look at the below mapping,
public class Zip {
#ManyToOne
#JoinColumn(name = "country_code", referencedColumnName = "iso_code")
private Country country = null
#Column(name = "country_code")
private String countryCode;
}
Here we are referring to the same column in the table using two different properties. In the below code,
Zip z = new Zip();
z.setCountry(getCountry("US"));
z.setCountryCode("IN");
saveZip(z);
What will Hibernate do here??
To prevent these kind of inconsistency, Hibernate is asking you to specify the update point of relationships. Which means you can refer to the same column in the table n number of times but only one of them can be used to update and all others will be read only.
2. Why is Hibernate complaining about your mapping?
In your Zip class you are referring to the Embedded id class ZipId that again contains the country code. As in the above scenario now you have a possibility of updating the country_code column from two places. Hence the error given by Hibernate is proper.
3. How to fix it in your case?
No. Ideally you want your ZipId class to generate the id, so you should not add insertable = false, updatable = false to the countryCode inside the ZipId. So the fix is as below modify the country mapping in your Zip class as below,
#ManyToOne
#JoinColumn(name = "country_code", referencedColumnName = "iso_code",
insertable = false, updatable = false)
private Country country;
Hope this helps your understanding.

You can also solve this problem by using #PrimaryKeyJoinColumn annotation . The PrimaryKeyJoinColumn annotation specifies a primary key column that is used as a foreign key to join to another table.
The PrimaryKeyJoinColumn annotation is used to join the primary table of an entity subclass in the JOINED mapping strategy to the primary table of its superclass; it is used within a SecondaryTable annotation to join a secondary table to a primary table; and it may be used in a OneToOne mapping in which the primary key of the referencing entity is used as a foreign key to the referenced entity.
If no PrimaryKeyJoinColumn annotation is specified for a subclass in the JOINED mapping strategy, the foreign key columns are assumed to have the same names as the primary key columns of the primary table of the superclass.