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Problem in <many-to-one> relationship

Sai Kiran nukala
Greenhorn

Joined: Aug 16, 2009
Posts: 9
Hi friends i got a problem in specifying many to one relationship....i have two tables

1. Usertable
2. Country Table

Usertable has user_id,user_name,user_password,country_id (country_id is a FK,which is PK in Country table)

Country has country_id, country_name

I wrote two classes one for usertable and other for country table.

User class:




Country Class:


Mapping files:

Country mapping file:


User Mapping file:



This is how I'm setting the data and inserting: (I mentioned only the necessary code)





Now the actual problem is country table has the data already. so when a new user registers I need to place the values into the Usertable without inserting new values into the country table. But when i insert the data into the Usertable this is the error i'm getting




The important thing is when I insert the data it is asking for the country_id which i already set the value in the Country object of User Class this we can
see that java code which i used above to insert the values into the Database. It is not using the country id which I already set in the Country object....Why?? Did i made any mistake in mentioning <many-to-one> relation???can you all help me??it is urgent I'm stuck here....

Thanks in advance...waiting for your valuable replies friends...and don't mind for the very long code I posted....I mentioned everything what I wrote.


Mark Spritzler
ranger
Sheriff

Joined: Feb 05, 2001
Posts: 17259
    
    6

remove the

insert="false" update="false"

those are about the country_id field in the user_table, you do want that to be set when you do an insert or an update on a User object. It is the Cascade mapping that determines how Country objects are saved when saving a User object and you already have it set to none.

Mark


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Sai Kiran nukala
Greenhorn

Joined: Aug 16, 2009
Posts: 9
Thanks Mark it is working now...thanks a lot......
Sai Kiran nukala
Greenhorn

Joined: Aug 16, 2009
Posts: 9
Thanks Mark it is working now...thanks a lot......and if you don't mind can you suggest me a book or tutorial where i can learn completely about the relationships in hibernate??
Mark Spritzler
ranger
Sheriff

Joined: Feb 05, 2001
Posts: 17259
    
    6

Sai Kiran nukala wrote:Thanks Mark it is working now...thanks a lot......and if you don't mind can you suggest me a book or tutorial where i can learn completely about the relationships in hibernate??


I recommend two books. First for beginning out and learning the basics is "Hibernate Made Easy" by our own bartender Cameron McKenzie.

Then for a full feature of everything in Hibernate, "Java Persistence with JPA" The Manning In Action book written by the Hibernate guys.

Mark
Sai Kiran nukala
Greenhorn

Joined: Aug 16, 2009
Posts: 9
Thanks mark.....I will do that....
Gadi Sh
Greenhorn

Joined: Oct 25, 2010
Posts: 2
Thanks Mark !

In my case removing the insert="false" update="false" fixed the problem.

 
 
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