CODEWITHSUNDEEP
javasqlhibernate
ThereIsElse
ThereIsElse

Reputation: 153

Hibernate is updating instead of inserting, why?

I'm starting my adventure with Hibernate, so please be patient :) I want to make mapping for two tables, for example A and B. The relation beetwen A and B is one-to-many. I wrote this hbm.xml file: 

 <hibernate-mapping package="something">
   <class name="A" table="A">
   <id name="id" type="int" column="ID">
      <generator class="native" />
   </id>
   <set name="setInA" sort="natural" cascade="all" lazy="false">
     <key column="ANOTHER_ID"/>
     <one-to-many class="B" />
   </set>
   </class>

  <class name="B" table="B">
   <id name="anotherId" type="int" column="ANOTHER_ID">
      <generator class="native" />
   </id>
   </class>
</hibernate-mapping>

Of course I made also POJO classes A and B.

And now, when I try to do:

A a = new A();
Set<B> set = new TreeSet<B>();
set.add(new B());
a.setSetInA(set);
session.save(a);

Hibernate inserts new row to table A, but (what is the worst) is not inserting new row to B table, but only makes SQL Update on not existing row in B. Can tell me anyone why it is happening? What I made wrong?

Upvotes: 2

Views: 4527

Answers (3)

Sven Rosvall
Sven Rosvall

Reputation: 1

Found this question while searching for causes of the same symptoms in my system. cascade="all" did not help.

In my case I solved this by adding a mapping to the list element, in this example class B.

Please note that the enclosing class (A in this example) also was versioned. Hibernate might require that versioning (used for optimistic locking) must be enabled for all nested elements. I haven't found any documentation to support this theory.

Upvotes: 0

Alex Barnes
Alex Barnes

Reputation: 7218

You can use Cascade without using annotations:

<set name="setInA" sort="natural" cascade="all" lazy="false" cascade="all">
     <key column="ANOTHER_ID"/>
     <one-to-many class="B" />
   </set>

This will ensure that collection of B instances is inserted when you insert A.

Upvotes: 0

Vladimir Ivanov
Vladimir Ivanov

Reputation: 43098

You should either persist B's objects firstly, or use Cascade option.

Upvotes: 3

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