Re: Storing properties in a logical way.
От | Daniel M. |
---|---|
Тема | Re: Storing properties in a logical way. |
Дата | |
Msg-id | 413CBC77.7060806@nm.ru обсуждение исходный текст |
Ответ на | Re: Storing properties in a logical way. (Pierre-Frédéric Caillaud<lists@boutiquenumerique.com>) |
Список | pgsql-sql |
On Sun, 05 Sep 2004 19:51:44 +0200, Pierre-Frédéric Caillaud <lists@boutiquenumerique.com> wrote: >> But after looking closely at the list of a possible properties, i found>> out that some of them depend on others. Forexample, if item is a>> PDF document, it can have an index. But a document can also have an>> index with links. Logically,a properties like 'index with links'>> don't belong to the verification table - they look like a kind of>> a compositefield - 'index with links' is not a stand-alone property,>> but it also implies that an item also has an 'index'property.>> On the other hand, it is impossible to decouple 'index' from>> 'with links', because the second part won'thave any meaning without>> the first part.>> You mean your properties would be better organized as a tree ?> Oris it even more complicated than that ? I never thought about that possibility - it is an interesting idea, and it solves the logical problem (though there is still a need to ensure that if child property is set, that the user won't be able to also set a parent property - which is probably implementable by using triggers). Though I would prefer, if it is possible, something much simpler, because there are only about 10 properties and 2 'composite' properties - it would probably be an overkill to create a tree for such a small table if a simpler solution exists. Daniel.
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