problem with table structure

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От Miguel Vaz
Тема problem with table structure
Дата
Msg-id AANLkTikOmfpOphzhysCD1OYM40pJwb922bCZbG9oSATD@mail.gmail.com
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Ответы Re: problem with table structure  (Alban Hertroys <dalroi@solfertje.student.utwente.nl>)
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Hi,

I am having some uncertainty while designing the following structure:

I have two sets of data:


* arqueology sites (can be natural):

id
name
description
id_category
id_period
x
y


* natural sites (can be arqueological also - bear with me -, so there will be duplicate records in the above table and this):

id
name
description
altitude
x
y

and i would like to put these two "sites" in the same data set and maybe add a new table called "site types" to categorize each record (maybe a relation table to allow many to many): how can i go about doing it? is this solution decent enough:

* sites (generic):

id_site
name
description
x
y


* site_natural
id
id_site
altitude

* site_arqueology
id
id_site
id_category
id_period

But i seem to be missing something. How can i have this in a way that its easy to list only "arqueology sites" for example. I feel the solution is simple enough, even for me, but its eluding me. Any help in the right direction would be very appreciated.

Thanks

Pag



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