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From Marc Prud'hommeaux <mprud...@apache.org>
Subject Re: How to write it in JPQL
Date Wed, 10 Jan 2007 20:16:15 GMT

That seems reasonable enough. Unfortunately, the JPQL query  
specification disallows anything but aggregate or state field  
expressions in "SELECT NEW" clauses.

It might be useful as a future extension to OpenJPA, though. Can you  
file an enhancement request at http://issues.apache.org/jira/browse/ 
OPENJPA ?


On Jan 10, 2007, at 2:39 AM, wanyna wrote:

>
> There are two tables A and B, I need to execute sql like
> "insert into A select ... from B".
> I use JPQL Constructor Expressions,
> select new A(...) from B, got A list then persist.
> But some data of A depends on program context, not from B, for simple
> example:
> select new A(B.column1, 'xxx') from B,
> select new A(null, B.column2) from B,
> select new A(variable, B.column2) from B
>
> I have to get the result object[] list and constuct A in my code now.
> I hope JPQL Constructor Expressions became more powerful, my code  
> will be
> more simple then.
>
>
>
>
> Marc Prud wrote:
>>
>>
>> On Jan 10, 2007, at 12:12 AM, wanyna wrote:
>>
>>>
>>> Hi all.
>>> I have two questions:
>>> 1.
>>> Here is my sql string:
>>> select 'xxx', TABLE_A.column1 from TABLE_A;
>>> there is a string 'xxx' as a constant value,
>>> how to translate it to JPQL?
>>
>> I don't think it is possible. Why would you need to do that?
>>
>>> 2.
>>> Another sql used under oracle:
>>> select TABLE_A.column1 from TABLE_A where rownum<10;
>>> how to limit range of result in JPQL or jpa?
>>
>> Query q = em.createQuery("select ...");
>> q.setFirstResult(0);
>> q.setMaxResults(10);
>> List results = q.getResultList();
>>
>>
>>
>>> --  
>>> View this message in context: http://www.nabble.com/How-to-write-it-
>>> in-JPQL-tf2951160.html#a8253611
>>> Sent from the open-jpa-dev mailing list archive at Nabble.com.
>>>
>>
>>
>>
>
> -- 
> View this message in context: http://www.nabble.com/How-to-write-it- 
> in-JPQL-tf2951160.html#a8255355
> Sent from the open-jpa-dev mailing list archive at Nabble.com.
>


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