foreign key constraint fails
deleting Child collection from Parent/Child relationship
This uses a bidirectional one to many association with cascades to model a parent / child relationship
http://www.hibernate.org/hib_docs/v3/re ... child.html

Hibernate version: 3.2

Mapping documents:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping
schema="hfydb"
default-cascade="save-update, delete"
auto-import="true"
package="domain"
default-lazy="false">

<class
name="domain.Property"
table="property"
>

<id
name="id"
type="java.lang.Integer"
column="property_id"
>
<generator class="increment" />
</id>

<many-to-one name="office" class="Office" column="office_id" cascade="none" />
<many-to-one name="style" class="Type" column="type_id" cascade="none" />
<many-to-one name="address" class="Address" column="address_id" cascade="all" />

<!-- http://www.hibernate.org/hib_docs/v3/re ... child.html
the Room entity is managing the FK property_id link,
the inverse attribute tells the collection not to update the link.
all-delete-orphan: a Child can't really exist without its parent
-->
<!-- one-to-many association between Property and Room -->
<set name="rooms" table="room" inverse="true" cascade="all-delete-orphan" >
<key column="property_id" />
<one-to-many class="Room" />
</set>

<property
name="appearOnPublic"
type="java.lang.Boolean"
column="public_access"
/>

<property
name="price"
type="java.lang.Integer"
column="price"
/>

</class>
</hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping
schema="hfydb"
default-cascade="save-update, delete"
auto-import="true"
package="domain"
default-lazy="false">

<class
name="domain.Room"
table="room"
>

<id
name="id"
type="java.lang.Integer"
column="room_id"
>
<generator class="increment" />
</id>

<!-- Make FK property_id part of the mapping -->
<many-to-one name="property" class="Property" column="property_id" not-null="true" />
<many-to-one name="type" class="Type" column="type_id" cascade="none" />

<property
name="name"
type="java.lang.String"
column="name"
not-null="true"
length="30"
/>

</class>
</hibernate-mapping>

Code between sessionFactory.openSession() and session.close():
Session session = _factory.openSession();
Property p = new Property();
session.delete(p);
session.flush();
/*Close session */
session.close();
Full stack trace of any exception that occurs:
Hibernate: delete from hfydb.property where property_id=?
15:03:02,609 DEBUG AbstractBatcher:476 - preparing statement
15:03:02,609 DEBUG AbstractEntityPersister:2391 - Deleting entity: [domain.Address#2]
15:03:02,625 DEBUG AbstractBatcher:44 - Executing batch size: 1
15:03:02,687 DEBUG AbstractBatcher:366 - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
15:03:02,687 DEBUG AbstractBatcher:525 - closing statement
15:03:02,687 DEBUG ConnectionManager:266 - skipping aggressive-release due to flush cycle
15:03:02,687 DEBUG JDBCExceptionReporter:63 - Could not execute JDBC batch update [delete from hfydb.property where property_id=?]
java.sql.BatchUpdateException: Cannot delete or update a parent row: a foreign key constraint fails (`hfydb/room`, CONSTRAINT `FK3580DB4834C3A4` FOREIGN KEY (`PROPERTY_ID`) REFERENCES `property` (`PROPERTY_ID`))

Name and version of the database you are using:
mysql
The generated SQL (show_sql=true):
15:03:02,609 DEBUG SQL:393 - delete from hfydb.property where property_id=?
Debug level Hibernate log excerpt:


Problems with Session and transaction handling?

Read this: http://hibernate.org/42.html

i remember reading something somewhere talking abt this. if I remember correctly, you have to do this in DB.

some like this:
CREATE TABLE child (id INT, parent_id INT,
INDEX par_ind (parent_id),
FOREIGN KEY (parent_id) REFERENCES parent(id)
ON DELETE CASCADE