Please, help me..

I cannot solve my problem during 3 days..

So, i have 2 tables (CoffeeOrder and CoffeeOrderItem), 1:M, bidirectional.

(1) Scripts for creating tables

create table CoffeeOrder (
id int not null, -- pk
type_id int not null, --
order_date datetime not null, --
name varchar(100), --
delivery_address varchar(200) not null, --
cost double, --
primary key (id)
) type=InnoDB;

create table CoffeeOrderItem (
id int not null, -- pk
order_id int not null, --
quantity int, --
primary key (id)
) type=InnoDB;

create index COI_I on CoffeeOrderItem (
order_id asc
);

-- FK
alter table CoffeeOrderItem
add constraint COI_CO foreign key (order_id)
references CoffeeOrder (id);


(2) My mapping files

Map for Order class

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping
PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
<class name="task.Order" table="CoffeeOrder" dynamic-update="true">

<id name="id" type="int"
unsaved-value="null">
<column name="id" sql-type="int"
not-null="true"/>
<generator class="assigned"/>
</id>
<bag name="children" inverse="true" cascade="all" lazy="true">
<key column="order_id"/>
<one-to-many class="task.OrderItem"/>
</bag>
<property name="type_id">
<column name="type_id" sql-type="int"
not-null="true"/>
</property>

<property name="order_date">
<column name="order_date" sql-type="datetime"
not-null="true"/>
</property>

<property name="name">
<column name="name" sql-type="varchar(100)"
not-null="false"/>
</property>

<property name="delivery_address">
<column name="delivery_address" sql-type="varchar(200)"
not-null="false"/>
</property>

<property name="cost">
<column name="cost" sql-type="double"
not-null="true"/>
</property>

</class>
</hibernate-mapping>

Map for OrderItem class

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping
PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
<class name="task.OrderItem" table="CoffeeOrderItem" dynamic-update="true">

<id name="id" type="int"
unsaved-value="null">
<column name="id" sql-type="int"
not-null="true"/>
<generator class="assigned"/>
</id>

<many-to-one name="order_id" class="task.Order" column="order_id" not-null="true"/>

<property name="quantity">
<column name="quantity" sql-type="int"
not-null="true"/>
</property>
</class>
</hibernate-mapping>


(3) My Classes...

public class Order implements java.io.Serializable{
....
public List getChildren() { return children; }
public void addChild(OrderItem child){
child.setOrder_id(this);
children.add(child);
}
public void setChildren(List children) { this.children=children; }
public void setId(int id){
this.id = id;
}
.... getter(), setter()
}

public class OrderItem implements java.io.Serializable{
private int id;
private Order order_id;
private int quantity;

public OrderItem(){}
.... getter, setter();
}


(4) Error description:

Exception happen when i execute this code (when adding Order to database):

sess = sf.openSession();
Order order = new Order();
order.setId(8);
order.setType_id(8);
order.setCost(777.0);
order.setOrder_date(Calendar.getInstance());
order.setName("my name");
order.setDelivery_address("my addr");
order.setChildren(new ArrayList());
try{
sess.save(order);
sess.flush();
}
catch(Exception ex)
{System.out.println(ex);}
sess.close();

This exception (and generated SQL):

[java] Hibernate: insert into CoffeeOrder (type_id, order_date, name, deliv
ery_address, cost, id) values (?, ?, ?, ?, ?, ?)
[java] Jul 16, 2004 10:56:08 AM net.sf.hibernate.util.JDBCExceptionReporter
logExceptions
[java] WARNING: SQL Error: 1216, SQLState: S1000
[java] Jul 16, 2004 10:56:08 AM net.sf.hibernate.util.JDBCExceptionReporter logExceptions
[java] SEVERE: General error message from server: "Cannot add or update a child row: a foreign key constraint fails"

I don't understand, what Hibernate Update?? I add only empty Order without childs..
This exception appear even if i set cascade="none"...

But i can read data from database, and exception not occured:

try{
Query query =
sess.createQuery("select item from task.Order as item");
List list = query.list();
Iterator iterator = list.iterator();
while(iterator.hasNext()){
Order p = (Order)iterator.next();
System.out.println(p);
java.util.List chld = (java.util.List)p.getChildren();
else{
Iterator it = chld.iterator();
while(it.hasNext()){
System.out.println((OrderItem)it.next());
}
}//else
}


Help me, please.

Best thanks..

Looked in glance... It is strange... should work.
on http://www.hibernate.org/hib_docs/reference/en/html/collections.html#collections-onetomany
wrote


As I see you use bidirectional association, and everything should be fine, you also bind your children to the parent in


But what is wrong? ...
For test try to remove NOT NULL constraint for CoffeeOrderItem.order_id,
let it be:

And at first try without index for CoffeeOrderItem.order_id.

--
Leonid

I have this method in Order:


And in OrderItem:


Even if i add children to Order:



This exception occuire..

I cannot allow order_id = NULL.

Try for test without NOT NULL constraint and look if it works.