one hibernate select generating lot of sql statement when using property-ref

(This is in a sense a follow up to my question http://www.experts-exchange.com/Programming/Programming_Languages/Java/Q_21396914.html#13879622
which was successfully answered. The difference in this case is that the association that's resulting in multiple SQL statements being generated is mapped using a property-ref attribute, and the solution to the question mentioned above does not seem to work in this case.)

Anyhow, here the problem:
I have a class called Po, a member of which has an associated RfqReqs. The latter has a field that keeps track of this relationship. So the Po class mapping has the following line: <one-to-one name="rfqReqs" class="RfqReqs" property-ref="reqPo"/>

while the RfqReqs class mapping has the following line:
<one-to-one name="rfqReqs" class="RfqReqs" property-ref="reqPo"/>

It is mapped that way based on the recommendation on page 221-222 of Hibernate in Action.

I have the RfqReqs class declared as lazy, so that it's not pulled up every time I do a find on a Po class. When I do need it, however, I retrieve it using the "left join fetch po.rfqReqs" as recommended in the answer to my question mentioned above, where, like here, I was looking for a way to prevent multiple SQL statements from being generated.

In this case, however, that solution does not seem to work: I still get multiple SQL statements generated as a result of the RfqReqs association and I suspect it has to do with the fact that I am using the property-ref attribute here.


Please help.


Hibernate version:
2.7

Mapping documents:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 2.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >
<hibernate-mapping package="com.talisen.lbwebpo.model">
<class name="RfqReqs" table="RFQ_REQS_TABLE" lazy="true">
<id name="rfqReqsId" column="RFQ_REQS_ID" type="integer">
<generator class="native"/>
</id>
<many-to-one name="reqPo" column="REQ_ID" class="Po" unique="true"/>
<many-to-one name="rfq" column="RFQ_ID" class="Rfq"/>
</class>
</hibernate-mapping>


<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >
<hibernate-mapping package="com.talisen.lbwebpo.model">
<class name="Po" table="PO_LIST" where="SOURCE != 'WEBPO - IDS' AND active = 1" lazy="true">
<id name="poId" column="PO_ID" type="integer">
<generator class="native"/>
</id>

<property name="parentPoId" column="PARENT_PO_ID" type="integer" />
<property name="poNumber" column="PO_NUMBER" type="string" not-null="true" />
<property name="changeOrderSeq" column="CHANGE_ORDER_SEQ" type="string" />
<property name="source" column="SOURCE" type="string" not-null="true" />
<property name="poDate" column="PO_DATE" type="date" not-null="true" />
<property name="loadDate" column="LOAD_DATE" type="date" not-null="true" />
<property name="filename" column="FILENAME" type="string" not-null="true" />
<property name="loadInfo" column="LOAD_INFO" type="string" />
<property name="creator" column="CREATOR" type="string" />
<property name="supplierName" column="SUPPLIER_NAME" type="string" />
<property name="supplierNumber" column="SUPPLIER_NUMBER" type="integer" />
<property name="buyerCode" column="BUYER_CODE" type="string" />
<property name="buyerDept" column="BUYER_DEPT" type="string" />
<property name="contract" column="CONTRACT" type="string" />
<property name="active" column="ACTIVE" type="byte" not-null="true" />
<property name="poTypeId" column="PO_TYPE_ID" type="integer" not-null="true"/>
<one-to-one name="rfqReqs" class="RfqReqs" property-ref="reqPo"/>
</class>
</hibernate-mapping>

Data Retrieval Code:
reqListForOneBuyerCode = session.find("from Po po left join fetch po.rfqReqs order by po.poDate asc where po.poTypeId=11 and po.buyerCode='" + buyerCode[i] + "'");
Full stack trace of any exception that occurs:
N/A

Database I'm using:
Oracle 9i

The generated SQL :
Hibernate: select po0_.PO_ID as PO_ID0_, rfqreqs1_.RFQ_REQS_ID as RFQ_REQS1_1_, po0_.PARENT_PO_ID as PARENT_P2_0_, po0_.PO_NUMBER as PO_NUMBER0_, po0_.CHANGE_ORDER_SEQ as CHANGE_O4_0_, po0_.SOURCE as SOURCE0_, po0_.PO_DATE as PO_DATE0_, po0_.LOAD_DATE as LOAD_DATE0_, po0_.FILENAME as FILENAME0_, po0_.LOAD_INFO as LOAD_INFO0_, po0_.CREATOR as CREATOR0_, po0_.SUPPLIER_NAME as SUPPLIE11_0_, po0_.SUPPLIER_NUMBER as SUPPLIE12_0_, po0_.BUYER_CODE as BUYER_CODE0_, po0_.BUYER_DEPT as BUYER_DEPT0_, po0_.CONTRACT as CONTRACT0_, po0_.ACTIVE as ACTIVE0_, po0_.PO_TYPE_ID as PO_TYPE_ID0_, rfqreqs1_.REQ_ID as REQ_ID1_, rfqreqs1_.RFQ_ID as RFQ_ID1_ from PO_LIST po0_ left outer join RFQ_REQS_TABLE rfqreqs1_ on po0_.PO_ID=rfqreqs1_.REQ_ID where po0_.SOURCE != 'WEBPO - IDS' AND po0_.active = 1 and ((po0_.PO_TYPE_ID=11 )and(po0_.BUYER_CODE='N1R' )) order by po0_.PO_DATE asc

And then this statement about twenty times:

Hibernate: select rfqreqs0_.RFQ_REQS_ID as RFQ_REQS1_2_, rfqreqs0_.REQ_ID as REQ_ID2_, rfqreqs0_.RFQ_ID as RFQ_ID2_, rfq1_.RFQ_ID as RFQ_ID0_, rfq1_.ISSUED_BY as ISSUED_BY0_, rfq1_.RELEASE_DATE as RELEASE_3_0_, rfq1_.BID_CLOSE_DATE as BID_CLOS4_0_, rfq1_.TAX_INFORMATION as TAX_INFO5_0_, rfq1_.FOB as FOB0_, rfq1_.SPECIAL_INSTRUCTIONS as SPECIAL_7_0_, rfq1_.RFQ_CONSTANT as RFQ_CONS8_0_, rfq1_.RFQ_BUYER_CODE as RFQ_BUYE9_0_, rfq1_.RFQ_BLUES_CODE as RFQ_BLU10_0_, rfq1_.RFQ_SEQ_REVISION_NUMBER as RFQ_SEQ11_0_, rfq1_.RFQ_STATUS as RFQ_STATUS0_, rfq1_.PO_ID as PO_ID0_, rfq1_.STATUS as STATUS0_, rfq1_.INCREMENTAL_PRICE_QUOTE as INCREME15_0_, rfq1_.PROCUREMENT_NOTES as PROCURE16_0_, po2_.PO_ID as PO_ID1_, po2_.PARENT_PO_ID as PARENT_P2_1_, po2_.PO_NUMBER as PO_NUMBER1_, po2_.CHANGE_ORDER_SEQ as CHANGE_O4_1_, po2_.SOURCE as SOURCE1_, po2_.PO_DATE as PO_DATE1_, po2_.LOAD_DATE as LOAD_DATE1_, po2_.FILENAME as FILENAME1_, po2_.LOAD_INFO as LOAD_INFO1_, po2_.CREATOR as CREATOR1_, po2_.SUPPLIER_NAME as SUPPLIE11_1_, po2_.SUPPLIER_NUMBER as SUPPLIE12_1_, po2_.BUYER_CODE as BUYER_CODE1_, po2_.BUYER_DEPT as BUYER_DEPT1_, po2_.CONTRACT as CONTRACT1_, po2_.ACTIVE as ACTIVE1_, po2_.PO_TYPE_ID as PO_TYPE_ID1_ from RFQ_REQS_TABLE rfqreqs0_ left outer join RFQ_TABLE rfq1_ on rfqreqs0_.RFQ_ID=rfq1_.RFQ_ID left outer join PO_LIST po2_ on rfq1_.PO_ID=po2_.PO_ID where rfqreqs0_.REQ_ID=?