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From Andrus Adamchik <and...@objectstyle.org>
Subject Re: auto-incrementing non-primary key field value needed
Date Tue, 23 May 2006 23:47:26 GMT
I was talking about PkGenerator.generatePkForDbEntity(DataNode,  
DbEntity) method (PkGenerator instance is owned by DbAdapter that is  
owned by DataNode). How you configure it is up to you. If you don't  
care about the gaps in values, and only care about them being unique,  
you can pass the real DbEntity to this method; if you want a separate  
sequence, you may fake a "synthetic" DbEntity and add an extra row to  
AUTO_PK_SUPPORT (or create an extra DB sequence if you are on oracle  
or postgres).

Andrus


On May 23, 2006, at 7:39 PM, Marcin Skladaniec wrote:
> On 24/05/2006, at 9:20 AM, Andrus Adamchik wrote:
>
>>
>> On May 22, 2006, at 10:27 PM, Mike Kienenberger wrote:
>>
>>> What's the best way to go about generating a non-primary-key
>>> auto-incrementing field value (unique, but eventually will be
>>> meaningful to the end users)?
>>>
>>> The database is Oracle (although I'd like it to work on HSQLDB too).
>>>
>>> Do I have to do this with a separate out-of-transaction database
>>> query, or is there some way I can make Cayenne assign a sequence  
>>> value
>>> to this column?
>>
>> Cayenne won't assign values to non-pk columns, but you can still  
>> reuse the Cayenne PK mechanism to obtain a sequence of values and  
>> set the values manually.
>>
>> Andrus
>
> Andrus, could you explain a bit how to use Cayenne PK mechanism ?  
> Would that require creating extra row in AUTO_PK_SUPPORT ? I would  
> like to use auto-incrementation on non PK field too.
>
> Thank you.
> Marcin
>
> -------------------------->
> ish
> http://www.ish.com.au
> Level 1, 30 Wilson Street Newtown 2042 Australia
> phone +61 2 9550 5001   fax +61 2 9550 4001


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