Re: generic modelling of data models; enforcing constraints dynamically...

Second glance: brilliant again! Even support for indexing is available; nice
job.
I found the hstore.sql -- that will add type, functions and stuff to my db.

I will give it a serious try!

Rob

2009/9/28 InterRob <rob(dot)marjot(at)gmail(dot)com>

> At first glance: brilliant! I was about to implement this key/value thing
> with an XML type... I will take a closer look at this, thanks a lot, Oleg!
> Tips & tricks to get this going in PostgreSQL?
>
>
> Rob
>
> 2009/9/28 Oleg Bartunov <oleg(at)sai(dot)msu(dot)su>
>
> Have you considered contrib/hstore to build flexible database scheme ?
>>
>> Oleg
>>
>> On Sun, 27 Sep 2009, InterRob wrote:
>>
>> Dear David, dear Peter, dear all,
>>> Peter, I was happy reading your reply right after I opened and read
>>> Davids.
>>> I do think I am on the right track; it is not a matter of building the
>>> one-and-only right schema, not in this case. Archaeology has the same
>>> twist
>>> as has ethnography, antropology and alike: they work with (what I would
>>> call) "narratives" (in fact, in the case of archaeology this seems to me
>>> to
>>> be an archaeologists monologue...). They try to support their findings
>>> with
>>> statistics and other means of quatification -- as does this modern,
>>> rationalist world require them to do, to be taken seriously as science...
>>> I
>>> seek to implement all this in a hybrid form; a fusion between the
>>> relational
>>> and EAV concept.
>>>
>>> Peter, may I invite you to privately share some more details on the
>>> system
>>> you are using and the design of it? Did you implement it using
>>> PostgreSQL?
>>> Looking forward to your reply.
>>> (And with respect to your previous message: whom are you actually
>>> referring
>>> to by the acronym "OPs"?)
>>>
>>> Cheerz,
>>>
>>>
>>> Rob
>>>
>>> 2009/9/27 Peter Hunsberger <peter(dot)hunsberger(at)gmail(dot)com>
>>>
>>> On Sun, Sep 27, 2009 at 2:22 PM, David Fetter <david(at)fetter(dot)org> wrote:
>>>>
>>>>> On Sun, Sep 27, 2009 at 08:26:27PM +0200, InterRob wrote:
>>>>>
>>>>>> Dear David, dear all,
>>>>>> I very well understand what you are saying...
>>>>>>
>>>>>
>>>>> Clearly you do not. What you are proposing has been tried many, many
>>>>> times before, and universally fails.
>>>>>
>>>>
>>>> I've been refraining from jumping on this due to time constraints, but
>>>> this statement is silly. We have a system that does almost exactly
>>>> what the OP wants although the implementation is slightly different:
>>>> we use an EAV like model with strong typing and build set / subset
>>>> forests to maintain arbitrary hierarchies of relationships. Our
>>>> reasons for doing this are similar to the OPs; it's for research (in
>>>> our case medical research). We maintain over 200,000 pieces of end
>>>> user generated metadata, describing what would be in a conventional
>>>> relational model over 20,000 columns and some 1,000s of tables but the
>>>> actual physical model is some 40 tables. Yes, the flip side is, such
>>>> a system won't support more than 1,000,000s of transactions per day,
>>>> but that's not why you build them.
>>>>
>>>>
>>>>> That your people are failing to get together and agree to a data model
>>>>> is not a reason for you to prop up their failure with a technological
>>>>> "fix" that you know from the outset can't be made to work.
>>>>>
>>>>>
>>>> Spoken like someone who has always had the luxury of working in areas
>>>> with well defined problem domains... I can't tell you the number of
>>>> people that told us exactly the same thing when we started on it.
>>>> That was 8 years ago. Not only can such systems be built, they can be
>>>> made to scale reasonably well. You do need to understand what you are
>>>> doing and why: the costs can be high, but when it comes to research,
>>>> the benefits can far outweigh the costs.
>>>>
>>>> --
>>>> Peter Hunsberger
>>>>
>>>>
>>>>
>>>
>> Regards,
>> Oleg
>> _____________________________________________________________
>> Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
>> Sternberg Astronomical Institute, Moscow University, Russia
>> Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
>> phone: +007(495)939-16-83, +007(495)939-23-83
>>
>>
>