SQLException - column name id0_ not found ???

sanjeevdg · **Joined:** Thu Feb 19, 2004 6:07 am **Posts:** 21

Hi all,

Hibernate newbie here. Was trying out some code and ran into
errors - my postgresql database gives me a SQLException when
I run my code. Says column name id0_ not found - when the
column name is actually id.
Actually I have three beans - foo, bar and snafu and all of them have
the id column - which seemed like a bad idea - since then I changed
the id columns to foo_id, bar_id and snafu_id - but the SQLException
is the same - only difference - now it says column foo_id0_ not found.

Please help.
Below are bean and hbm.xml files.

Code:

<?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>
    <class name="Foo" table="foo">
        <id name="foo_id" column="foo_id" type="int">
      
            <generator class="assigned"/>
        </id>

        <set name="barSnafus" table="foo_bar_snafu">
            <key column="f_id"/>
            <composite-element class="BarSnafu">
                <many-to-one name="bar" class="Bar" column="b_id"/>
                <many-to-one name="snafu" class="Snafu" column="s_id"/>
            </composite-element>
        </set>
    </class>
</hibernate-mapping>

___________________________________________________________

Code:

<?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>
    <class name="Bar" table="bar">
       <id name="bar_id" column="bar_id" type="int">
            <generator class="assigned"/>
        </id>
    </class>
</hibernate-mapping>

___________________________________________________________

Code:

<?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>
    <class name="Snafu" table="snafu">
        <id name="snafu_id" column="snafu_id" type="int">
            <generator class="assigned"/>
        </id>
    </class>
</hibernate-mapping>

___________________________________________________________

Code:

import java.util.Set;
import java.io.Serializable;

public class Foo implements Serializable
{
    protected int foo_id;
    protected Set set;

    public Foo()
    {
    }

    public int getFoo_id()
    {
        return foo_id;
    }

    public void setFoo_id(int foo_id)
    {
        this.foo_id = foo_id;
    }

    public Set getBarSnafus()
    {
        return set;
    }

    public void setBarSnafus(Set set)
    {
        this.set = set;
    }
}

___________________________________________________________

Code:

import java.io.Serializable;



public class Bar implements Serializable
{
    protected int bar_id;

    public Bar()
    {
    }

    public int getBar_id()
    {
        return bar_id;
    }

    public void setBar_id(int bar_id)
    {
        this.bar_id = bar_id;
    }
}

___________________________________________________________

Code:

import java.io.Serializable;



public class Snafu implements Serializable
{
    protected int snafu_id;

    public Snafu()
    {
    }

    public int getSnafu_id()
    {
        return snafu_id;
    }

    public void setSnafu_id(int snafu_id)
    {
        this.snafu_id = snafu_id;
    }
}

___________________________________________________________

Code:

import java.io.Serializable;


public class BarSnafu implements Serializable
{
    protected Bar bar;
    protected Snafu snafu;

    public BarSnafu()
    {
    }

    public Snafu getSnafu()
    {
        return snafu;
    }

    public void setSnafu(Snafu snafu)
    {
        this.snafu = snafu;
    }

    public Bar getBar()
    {
        return bar;
    }

    public void setBar(Bar bar)
    {
        this.bar = bar;
    }

    public String toString()
    {
        return bar.getBar_id() + ", " + snafu.getSnafu_id();
    }
}

___________________________________________________________

I'd be very much obliged if anyone could point out what mistake I'm making.
Thanks.
sanjeev.

emmanuel · **Posted:** Thu Feb 19, 2004 7:03 am

Show the SQL request and the DDL.

sanjeevdg · **Joined:** Thu Feb 19, 2004 6:07 am **Posts:** 21

Ok - the ddl is like this:

create table foo(foo_id int);
create table bar(bar_id int);
create table snafu(snafu_id int);
create table foo_bar_snafu(f_id int, b_id int, s_id int);

The problem I figured out is in the sql query string i'm passing.
I corrected the error and it now works beautifully.

select f.* from Foo as f //This wasn't working
select f.id as id0_ from Foo as f // This is.

However I have one more question - I can access the data in tables -
foo, bar and snafu because I loaded these classes onto the config.
But data in table foo_bar_snafu - I'm unable to access - I mean how
would I access it ? I have a relation like BarSnafu but I don't know how it
works - Stupid question - i know - but i'd really like some pointers on
how to get myself up-to-date. Your 2 cents would be of immeasurable value to me.

sanjeevdg · **Joined:** Thu Feb 19, 2004 6:07 am **Posts:** 21

er - bump.

emmanuel · **Posted:** Fri Feb 20, 2004 7:14 am

http://www.hibernate.org/hib_docs/reference/html_single/#query-language
elements(), indices(), [], etc...

Code:

from foo join foo.barSnafu snafu...