Question

I m using one-to-many mapping for List using join table.
There are lot of examples available on net of this mapping using Sets but not with Lists.

Consider tables:

Table Ticket
{
ticketid int PK;
...
}

Table Attachment
{
attachmentid int PK;
...
}

Join Table:

Ticket_Attachment_Join
{
tid  FK (ref to Ticket.ticketid)
aid PK FK(ref to Attachment.attachmentid)
}

Mappings:
Ticket.hbm.xml:

    <hibernate-mapping>
    <class name="Tickets" table="Ticket">
    ...
    <list name="attachmentsList" table="Ticket_Attachment_Join" cascade="save-update">
            <key column="ticketid"/>
           <list-index column="index_col"/>
            <many-to-many column="attachmentId" unique="true" class="Attachments" />
    </list>

...
</class>
</hibernate-mapping>

I want to ask that in which table i should put column index_col (<list-index...>column)? In Attachment table or in join table?? Is it neccessary to put index_col for lists in the table which represents lists(Here ‘Attachment’ table).

Answer 1

It should be on Ticket_Attachment_Join as it is the table you are refering to in list mapping.

 <list name="attachmentsList" table="Ticket_Attachment_Join" 
                                      cascade="save-update">

And if you don’t need any indexed collections you can map that attachmentsList using <bag> then you don’t need that <list-index column="index_col"/> mapping at all.