I am trying to map a one to many and many to many relation of Customer, Contact and Address. I have many to many relation with Customer and Address. one to many with Customer and Contact.
Each time I insert a record, I get three PK from a sequence. Say e.g. 11 for Customer, 12 for Address and 13 for Contact, For Address and Contact these keys are correct in both parent and child tables.
For Customer I dont know where the heck a key 14 is generated as PK, But in child tables Cust_id (FK to contact and address) is remain 11.

Please suggest me if there is something wrong with mapping. Also using hibernate should i setup the RI contraints in DB or in my mapping files.

Mapping Files are;

Customer:
------------

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class
name="com.wonder.common.Customer"
table="CUSTOMER">
<id
name="id"
type="long"
column="CUST_ID">
<generator class="sequence">
<param name="sequence">ID_SEQ</param>
</generator>
</id>
<property name="fName">
<column name="FIRST_NAME" />
</property>
<property name="lName">
<column name="LAST_NAME" />
</property>
<property name="gender">
<column name="GENDER" />
</property>
<property name="businessTitle">
<column name="BUSINESS_TITLE" />
</property>
<property name="customerNumber">
<column name="CUST_NO" />
</property>
<property name="regDate">
<column name="REG_DATE" />
</property>
<set
name="contact"
cascade="save-update,persist">
<key
column="CUST_ID"
not-null="true" />
<one-to-many
class="com.wonder.common.Contact"
entity-name="CustContacts" />
</set>
<set
name="address"
table="CUST_ADDRESS"
cascade="save-update,persist">
<key column="CUST_ID" not-null="true"/>
<many-to-many
column="ADDRESS_ID"
class="com.wonder.common.Address" />
</set>
</class>
</hibernate-mapping>


Contact:
---------

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class
name="com.wonder.common.Contact"
entity-name="EmpContacts"
table="EMP_CONTACT">
<id
name="id"
type="long"
column="CONTACT_ID">
<generator class="sequence">
<param name="sequence">ID_SEQ</param>
</generator>
</id>
<property name="homePhone">
<column name="HOME" />
</property>
<property name="officePhone">
<column name="OFFICE" />
</property>
<property name="mobile">
<column name="MOBILE" />
</property>
<property name="fax">
<column name="FAX" />
</property>
<property name="email">
<column name="EMAIL" />
</property>
</class>

<class
name="com.wonder.common.Contact"
entity-name="CustContacts"
table="CUST_CONTACT">
<id
name="id"
type="long"
column="CONTACT_ID">
<generator class="sequence">
<param name="sequence">ID_SEQ</param>
</generator>
</id>
<property name="homePhone">
<column name="HOME" />
</property>
<property name="officePhone">
<column name="OFFICE" />
</property>
<property name="mobile">
<column name="MOBILE" />
</property>
<property name="fax">
<column name="FAX" />
</property>
<property name="email">
<column name="EMAIL" />
</property>
</class>
</hibernate-mapping>


Address
----------

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class
name="com.wonder.common.Address"
table="ADDRESS">
<id
name="id"
type="long"
column="ADDRESS_ID">
<generator class="sequence">
<param name="sequence">ID_SEQ</param>
</generator>
</id>
<property name="Type">
<column name="TYPE" />
</property>
<property name="Street">
<column name="STREET" />
</property>
<property name="Road">
<column name="ROAD" />
</property>
<property name="City">
<column name="CITY" />
</property>
<property name="Postcode">
<column name="POSTCODE" />
</property>
<property name="Country">
<column name="COUNTRY" />
</property>
</class>
</hibernate-mapping>