Re: Dumb (?) subclass question

Thomas Ganter <[email protected]> Fri, 7 Jan 2005 11:04:11 +0100
Newsgroups gmane.comp.web.webobjects.eof
Message-ID <[email protected]>
Hi Chuck,

I can rule out to accidentially create duplicates. There is no way 
where this could happen.
And this reproducably happens for every single items() relationship I 
do on any arbitrary HEAD element.

In my EO subclass of ITEM, which is ITEM_E, I have entered the 
qualifier "(typ='E')" in the advanced entity inspector, with "typ" 
being a class property.

The idea is to have items() retrieve all ITEM elements, whereas 
item_es() only retrieve special ones.

Do I need to have a qualifier in the "ITEM" properties as well?

Greetings,

- Thomas

Am 07.01.2005 um 03:12 schrieb Chuck Hill:

> Yes, you probably did something wrong in setting up the subclass.  We 
> will need more details (single table, vertical, horizontal 
> inheritance) to discern why.  As a guess, you forgot the restricting 
> qualifier.
>
> If not that, then  perhaps you are manually adding a duplicate in your 
> code though incorrect use of EOF?
>
> Chuck
>
>
> On Jan 6, 2005, at 5:08 PM, Thomas Ganter wrote:
>
>> Hi all,
>>
>> I just spent four hours searching for a bug when I found a situation 
>> in which a to-many relationship always contained duplicate elements.
>> I always was under the impression that the array I get will contain 
>> distinct rows and never checked for duplicates.
>>
>> Let's say there are two tables: HEAD and ITEM with a 1:n relationship.
>>
>> Whenever I say (HEAD)h.items(), I get four entries in the NSArray 
>> when in the database there are only three.
>>
>> Could this be somehow due to the fact that i sublassed ITEM?
>>
>> If so, how can I prevent this behaviour?
>>
>> Greetings,
>>
>> - Thomas
>>
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