JBoss Community

hello Hibernate gurus!

I would like to improve my app performance through HQL optimzation.

I have a small example to show my problem:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

    <class name="hibernate.classes.Peoples" table="PEOPLES" catalog="Dev1">

            <id name="PId" type="int">

                <column name="P_ID" />

                <generator class="identity"/>

            </id>

            <property name="pfirstname" type="string">

                <column name="p_firstname" />

            </property>

            <property name="plastname" type="string">

                <column name="p_lastname" />

            </property>

            <property name="phobby" type="string">

                <column name="p_hobby" />

            </property>

          <many-to-one name="address" class="hibernate.classes.Address" fetch="join" insert="false" update="false">

                      <column name="p_adress" not-null="true"/>

                  </many-to-one>

</class>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

    <class name="hibernate.classes.Address" table="ADDRESS" catalog="Dev1">

            <id name="AId" type="int">

                <column name="A_ID" />

                <generator class="identity"/>

            </id>

            <property name="street" type="string">

                <column name="a_street" />

            </property>

            <property name="house" type="string">

                <column name="a_house" />

            </property>

            <property name="district" type="string">

                <column name="a_district" />

            </property>

</class>

I'd like to display rows from people and also show the appropriate person's address (foreign key bind)

When i use HQL join like this way:

session.createQuery("from  Peoples inner join Address")

I suppose in this case .tolist() does not work properly becouse there are additional join properties.

When i use simple ("from Peopes") HQL query together with many-to-one default lazy="proxy" the result
will be terrible slow.
Hibernate try to gets seperatly every row from Address with foreign key selects. (May is it the N+1 Select problem?)

This is an impact when i have many rows in my table.

What is the best practice when i always want to display this cross joined datas? 

(pfirstname, plastname, phobby, street, house)

Should i use iterator and manually place each property from the query result?

Thanks in advance!
Sorry for the dummy question! :S