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How to make a JOIN without a directly mapped entity?

 
Greenhorn
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Hi people!

If I have for example two entities, Client and Product, in product entity I have a relationship with client, so I have a @ManyToOne JPA relationship.

Client

Product
- client_id

But I wonder to make an "inverse" JOIN (left) query, because its possible under native SQL using <type> JOIN ON Table (id1 = id2), but how to figure out some situation under JPA?

If I heading doing something like that I got an error:



Because 'ON' clause is not allowed up there, I know that I can use other maner like:



But sometimes I have to use like an native SQL, to JOIN a entity that donĀ“t have directly link. Sorry If I was not clean in my ideas.

Regards!
 
Ranch Hand
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you might want to do something like

Select p.*, (Select c.<column> from Client c where c.id = p.id ) from Product p.

It will give the same result as when the join is Left Outer done from Product to Client..
 
Inocencio Oliveira
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Thank you Rahul, I will try this way soon and repley back here.
 
Inocencio Oliveira
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I did it, but I have some questions.

how can I test some conditions about client, like:



Thanks again!
 
Rahul Babbar
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Like this...
 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
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