I have a Tree like structure where top node is attached to multiple sub-nodes through an association table(many-to-many relationship). This can go down upto 3-4 levels.
I want to load the complete tree in one go.
My problem is that even with 3-4 rows in one table, Hibernate issues 25-30 sqls. Utimately we will have few thousands of rows.
Can you please help in this as I am new to Hibernate.
I am using Hiberante V2.1.4 and DB is DB2 7.1

I am issuing a simple query like
Query q = hibSession.createQuery("select p from BasePid as p");

Thanks in advance

I am attaching my mappings doc

<hibernate-mapping package="com.myquest.model">

<class name="BasePid" table="BASE_PID" lazy="false" mutable="false">
<id name="nodeId" type="long" unsaved-value="0" >
<column name="PID_ID" sql-type="char(32)" />
<generator class="uuid.hex"/>
</id>


<property name="dispStyle">
<column name="PID_DSPL_STYL_CD"/>
</property>


<map name="lblMap" table="BASE_PID_I18N" outer-join="true">
<key column="PID_ID"/>
<index column="LCLE_CD" type="string"/>
<element column="LBL_TX" type="string"/>
</map>

<map name="childMap" table="BASE_PID_PID_SCTN" outer-join="true" order-by= "SCTN_SQ">
<key column="PID_ID"/>
<index column="SCTN_SQ" type="float"/>
<many-to-many class="BasePidSctn" column="PID_SCTN_ID" outer-join="true"/>
</map>

</class>


<class name="BasePidSctn" table="BASE_PID_SCTN" lazy="false" mutable="false">
<id name="nodeId" type="long" unsaved-value="0" >
<column name="PID_SCTN_ID" sql-type="char(32)" />
<generator class="uuid.hex"/>
</id>



<property name="dispStyle">
<column name="PID_DSPL_STYL_CD"/>
</property>


<map name="lblMap" table="BASE_PID_SCTN_I18N" outer-join="true">
<key column="PID_SCTN_ID"/>
<index column="LCLE_CD" type="string"/>
<element column="LBL_TX" type="string"/>
</map>
<map name="linksMap" table="BASE_PID_SCTN_LINK" outer-join="true">
<key column="PID_SCTN_ID"/>
<index column="LINK_SQ" type="float"/>
<element column="LINK_ID" type="long"/>
</map>
<map name="childMap" table="BASE_PID_SCTN_ELMN" outer-join="true"
order-by="CHLD_SQ" where = "CHLD_PID_SCTN_ID = 0 ">
<key column="PID_SCTN_ID"/>
<index column="CHLD_SQ" type="float"/>
<many-to-many class="BasePidElmn" column="PID_ELMN_ID" outer-join="true"/>
</map>

<map name="sctnMap" table="BASE_PID_SCTN_ELMN" outer-join="true"
order-by="CHLD_SQ" where = "CHLD_PID_SCTN_ID &lt;&gt; 0 ">
<key column="PID_SCTN_ID"/>
<index column="CHLD_SQ" type="float"/>
<many-to-many class="BasePidSctn" column="CHLD_PID_SCTN_ID" outer-join="true"/>
</map>

</class>


<class name="BasePidElmn" table="BASE_PID_ELMN" lazy="false" mutable="false">

<id name="nodeId" type="long" unsaved-value="0" >
<column name="PID_ELMN_ID" sql-type="char(32)" />
<generator class="uuid.hex"/>
</id>


<property name="dispStyle">
<column name="PID_DSPL_STYL_CD"/>
</property>


<property name="valSysName">
<column name="VL_SYST_NM"/>
</property>

<property name="valName">
<column name="VL_NM"/>
</property>


<map name="lblMap" table="BASE_PID_ELMN_I18N" outer-join="true">
<key column="PID_ELMN_ID"/>
<index column="LCLE_CD" type="string"/>
<element column="LBL_TX" type="string"/>
</map>
<map name="linksMap" table="BASE_PID_ELMN_LINK" outer-join="true">
<key column="PID_ELMN_ID"/>
<index column="LINK_SQ" type="float"/>
<element column="LINK_ID" type="long"/>
</map>

</class>

This is not possible in SQL, hence not in Hibernate. You would need a vendor specific procedural query, e.g. "select .. connect by..." in Oracle or "select recursive ..." in DB2. Use Session.createSQLQuery(). Another approach is the "nested set model", search Google.