Re: one-to-one schema design question and ORM

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От alexander krohn
Тема Re: one-to-one schema design question and ORM
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Msg-id 45F6B63E.9010600@e-dict.net
обсуждение исходный текст
Ответ на one-to-one schema design question and ORM  (Rick Schumeyer <rschumeyer@ieee.org>)
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hi.

Rick Schumeyer wrote:
> [...]
>  From a business rules perspective:
>   Some users are not employees (like an admin user)
>   Some employees are not users
> [...]
from my view users and employees have something in common: they are persons.

why don't create a person-table with the attributes the groups share, like a
login-name, etc.

then your users-table will have a primary-key that is also a foreign-key,
referencing the id in the person-table and the employees-table does the same.

when you want to get all user- and employee-accounts for one person you have to
build up a join on the tables. that's a simple view, don't know what your
favourite or-mapper thinks about it.

i think the above table-design can be considered 'clean' from some academic
point of view ;)

mfg

alexander

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