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Hi everyone this is my very first post so please ignore any mistakes and let me know if any

mahesh shastri
Greenhorn

Joined: Sep 04, 2010
Posts: 11

I am using Hibernate and postgrSQL in my project . I am in a situation where I need to do self-join for a table and I want to use
one- to-many relationship for that. Where my table contains few fields in which one of the field say x field contains the value of
primary key which can be null. Now sometimes I need to fetch records which have identical values in field x.
how do i configure this in hbm.xml ?


Thanks and Regards
Sai Hegde
security forum advocate
Ranch Hand

Joined: Oct 26, 2010
Posts: 199
    
    1

Use DetachedCriteria for the object and set the projection for the join field.

Code Snippet -

DetachedCriteria dc = DetachedCriteria.forClass(Table.class);
dc.add(Restrictions.eq("x", value1);
dc.setProjection(Property.forName("y"));
Criteria c = session.createCriteria(Table.class);

c.add(Property.forName("y").in(dc));
c.list();
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: Hi everyone this is my very first post so please ignore any mistakes and let me know if any
 
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