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From Patrick Linskey <plins...@gmail.com>
Subject Re: Unnecesery INNER JOIN
Date Fri, 16 Jul 2010 06:06:57 GMT
Hi,

This sounds like it might be another manifestation of https://issues.apache.org/jira/browse/OPENJPA-1711

-Patrick

On Jul 15, 2010, at 2:41 PM, Russell Collins wrote:

> From the looks of what you have in your query, there has to be a join of some kind. 
You are trying to get the "id" of class "A" that is associated with class "B".  If this is
not your desire, what are you trying to do?
> 
> -----Original Message-----
> From: QkI [mailto:kukismen@gmail.com]
> Sent: Thursday, July 15, 2010 8:19 AM
> To: users@openjpa.apache.org
> Subject: Unnecesery INNER JOIN
> 
> 
> Hi,
> Let's say I have the following persistence class:
> 
> @Entity
> public class B {
> 
>  @OneToOne(cascade = CascadeType.PERSIST, fetch = FetchType.LAZY)
>  @JoinColumn(name = "a_id")
>  private A a;
> }
> 
> and when I try to execute this JPA query:
> SELECT b.a.id FROM B where B.id = 123
> 
> my SQL output looks like:
> SELECT t1.id FROM table_b t0 INNER JOIN table_a t1 ON t0.a_id = t1.id WHERE
> (t0.id = 123)
> 
> Why does openJPA add unnecesery JOIN to the SQL query.
> Can I somehow change this behaviour of openJPA
> 
> Thanks,
> QkI
> 
> 
> --
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> 
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-- 
Patrick Linskey
202 669 5907


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