Problem generating many-to-one relation using reveng.xml

dip_cemk · **Joined:** Thu Jan 15, 2009 3:55 pm **Posts:** 12

Hello,
I'm trying to create 2 *.hbm files via reverse engineering.
My problem is, that the the hbm files are generated but without many-to-one relationship.

Code:

Used Env:
Eclipse:  3.4
Oracle: 9i
driver: ojdbc14.jar
hibernate: hibernate3.jar, hibernate-tools.jar

project.reveng.xml:

Code:

<table-filter match-name="ACFT_NOSE" match-schema="ODS_ADMIN1"></table-filter>
   <table-filter match-name="ACFT_TAIL" match-schema="ODS_ADMIN1">
</table-filter>
<table catalog="ODS_ADMIN1" schema="ODS_ADMIN1" name="ACFT_TAIL"
class="com.ual.ods.hibernate.test222.AcftTail">
<primary-key></primary-key>
</table>
<table catalog="ODS_ADMIN1" schema="ODS_ADMIN1" name="ACFT_NOSE"
class="com.ual.ods.hibernate.test222.AcftNose">
<foreign-key foreign-catalog="ODS_ADMIN1" constraint-name="MOTHER"
foreign-table="ACFT_TAIL" foreign-schema="ODS_ADMIN1">
<column-ref local-column="TAIL_NBR" foreign-column="TAIL_NBR" />
<many-to-one property="child"/>
</foreign-key>
</table>

hibernate.cfg.xml:

Code:

<hibernate-configuration>
    <session-factory>
         <property name="hibernate.bytecode.use_reflection_optimizer">false</property>
        <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
        <property name="hibernate.connection.password">pass</property>
        <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1531:db1</property>
        <property name="hibernate.connection.username">user</property>
        <property name="hibernate.default_schema">ODS_ADMIN1</property>
        <property name="hibernate.dialect">org.hibernate.dialect.Oracle9Dialect</property>
        <property name="hibernate.default_catalog">ODS_ADMIN1</property>
    </session-factory>
</hibernate-configuration>

Generated sample hbm:

Code:

<hibernate-mapping>
    <class name="com.ual.ods.hibernate.test222.AcftNose" table="ACFT_NOSE">
        <id name="noseNbr" type="java.lang.String">
            <column name="NOSE_NBR" length="4" />
            <generator class="assigned" />
        </id>
        <property name="tailNbr" type="java.lang.String">
            <column name="TAIL_NBR" length="6" />
        </property>
.
.

</class>
</hibernate-mapping>

----------------------------------------

but I expected:

Code:

<hibernate-mapping>
    <class name="com.ual.ods.hibernate.test222.AcftNose" table="ACFT_NOSE">
        <id name="noseNbr" type="java.lang.String">
            <column name="NOSE_NBR" length="4" />
            <generator class="assigned" />
        </id>


<many-to-one name="acftTail" class="com.ual.ods.hibernate.AcftTail" fetch="select">
<column name="TAIL_NBR" length="6" />
</many-to-one>
.
.

<
</class>
</hibernate-mapping>

Please help me out? I am stuck badly.

max · **Posted:** Mon Jan 19, 2009 6:00 am

remove schema and catalog from your reveng.xml since you already specified them as being the default. That might help.

dip_cemk · **Joined:** Thu Jan 15, 2009 3:55 pm **Posts:** 12

Hi Max,

You are perfect as always.
I have already done yesterday and guess what - it was exactally you suggested.
Thanks man once again.

-thanks,
Sudip Das

dip_cemk · **Joined:** Thu Jan 15, 2009 3:55 pm **Posts:** 12

Hi,

I was trying to map Tabel1[c1, c2, c3, c4] to Table2[cc1, cc2, cc3, cc4] in many-to-one using reveng.xml:

What should be the syntax for multiple columns (I am able to do it using one column):

I have done till:

Quote:

reveng.xml:

Code:

<table name="FA_SEG"> 
<foreign-key constraint-name="fkProp2" foreign-table="OPS_FLT_LEG">
<column-ref local-column="c1" foreign-column="cc1" />
<many-to-one property="segToOps" />
</foreign-key>
</table>

Can somebody please complete it?
I would expect to write something like that:

Code:

<table name="FA_SEG"> 
<foreign-key constraint-name="fkProp2" foreign-table="OPS_FLT_LEG">
<column-ref local-column="c1" foreign-column="cc1" />
<column-ref local-column="c2" foreign-column="cc2" />
...
...
<many-to-one property="segToOps" />
</foreign-key>
</table>

max · **Posted:** Tue Jan 20, 2009 2:28 am

yes - looks correct. what is the problem ?

dip_cemk · **Joined:** Thu Jan 15, 2009 3:55 pm **Posts:** 12

Hi Max,

The problem is Table2 is containing 2 more pk and I'm trying to do with only 2 (for right outer join).
So it is giving error,(which is expected):

Code:

org.hibernate.MappingException: Foreign key (FK7B33A2B1A54948B7:Table1[c1,c2])) must have same number of columns as the referenced primary key (Table2[cc1,cc2,cc3,cc4])

I can solve the problem by manual editing in Table2 like:

Code:

<properties name="FKMaps" insert="false" update="false">
<property name ...
..
..
</property>
</properties>

and then in Table1

Code:

<many-to-one name=...... property-ref="FKMaps">
<column ..>
 <column ..>

..
</many-to-one>

But I want to do it using reveng.xml.
Is it feasiable at all?

max · **Posted:** Tue Jan 20, 2009 8:46 am

reveng might not support partial primary key references (since the code generation would fail)

tried using database level constraints instead of reveng.xml ?

dip_cemk · **Joined:** Thu Jan 15, 2009 3:55 pm **Posts:** 12

Hi Max,

Unfortunately it can be done in database level - due to some dependency to other tables.

So, there is no other way to implement using reveng.xml the sql like:

Table1 right out join Table2
on Table1.c1 = Table2.cc1
and Table1.c2 = Table2.cc2
-where Table1 [PK(c8,c9)] and Table2 [PK (cc1,cc2,cc3,cc4)]

But I am able able to do it using manual editing the hbm files by defining:
1. <properties> tag in Table2 -- my choice of columns may not be the PK also.
2. And then property-ref in Table1 to map from Table1.columns to Table2.columns.

Is it some other way to do it?

-thanks,
Sudip Das

max · **Posted:** Wed Jan 28, 2009 5:48 pm

no, the reveng doesn't handle overlapping associations.