Hi,
i am currently searching for a solution of a problem with the Criteria API of Hibernate 3.2:
I have the following mapping:
Class A references a Set of class B.
Class B is an abstract class and has different extensions (B1, B2, ...). The inheritance is mapped via joined subclass using a discriminator.
All extensions of class B contain different properties.
The mapping of the abstract class B contains a property which references the discriminator column.
My problem:
I want to query all instances of class A which reference an instance of class B1 with the property B1.P1 set to "foo".
My current approach:
Code:
Criteria criteria = session.createCriteria(A.class);
Criteria subCriteria = criteria.createCriteria("setOfBs");
subCriteria.add(
Restrictions.and(
Restrictions.eq("discriminator", "B1"),
Restrictions.eq("P1", "foo")
)
);
criteria.list();
This criteria results in a SQL Exception:
Code:
org.hibernate.exception.SQLGrammarException: could not execute query
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:67)
at ...
Caused by: java.sql.SQLException: ORA-00904: "B_REF1_1_"."FOO": invalid identifier
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:331)
at ...
This exception is is thrown because hibernate creates a wrong select statement:
Code:
select
this_.a_id as a1_3_1_,
b_ref1_.b_id as a1_0_0_,
b_ref1_.discriminator as a2_0_0_,
b_ref1_.a_id as a3_0_0_,
b_ref1_1_.bar as a2_7_0_,
b_ref1_2_.foo as a2_8_0_,
b_ref1_3_.fnord as a2_9_0_,
from
t_a this_
inner join
t_b b_ref1_
on this_.a_id=b_ref1_.a_id
left outer join
t_b_1 b_ref1_1_
on b_ref1_.b_id=b_ref1_1_.b_id
left outer join
t_b_2 b_ref1_2_
on b_ref1_.b_id=b_ref1_2_.b_id
left outer join
t_b_3 b_ref1_3_
on b_ref1_.b_id=b_ref1_3_.b_id
where
(
b_ref1_.discriminator=?
and b_ref1_1_.foo=?
)
It would be correct if the where clause would look like that
Code:
where b_ref1_[b]2[/b]_.foo=?
Is there any possibility for a query on properties of references objects in a inhertiance hierachy using the criteria API?
Thanks in advance
i.
Login
FAQ
Search