Re: Fwd: Re: Referencing
От | lucas@presserv.org |
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Тема | Re: Fwd: Re: Referencing |
Дата | |
Msg-id | 20051028130720.jxoth8izb468k44s@www.presserv.org обсуждение исходный текст |
Ответ на | Re: Fwd: Re: Referencing (Daryl Richter <daryl@brandywine.com>) |
Ответы |
Re: Fwd: Re: Referencing
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Список | pgsql-sql |
Quoting Daryl Richter <daryl@brandywine.com>: > It's hard to say without knowing more precisely what you are trying > to model, but I think this push you in the right direction: > > -- This table takes the place of both SEND and BUY > create table activity( > id serial primary key, > product_id integer, --references.... > value money > ); > > create table financial( > id serial primary key, > cred_deb smallint, > value money, > activity_id integer references activity > ); > > create table output( > id serial primary key, > client integer, --references clientes, > fiscal_number varchar(30), > print_date date, > activity_id integer references activity > ); > > create table input( > id serial primary key, > supplier integer, -- references suppliers, > employee varchar(30), > activity_id integer references activity > ); > > And then you do the following: > > create view buy > as > select > a.id, > b.id as "input_id", > a.product_id, > a.value > from > activity a > join input b on b.activity_id = a.id; > Okay, but references between (output/input) and ACTIVITY tables is 1 to N. OUTPUT/INPUT - 1 to ACTIVITY - N. And not N to 1 how the example. Then the reference field need to be on "ACTIVITY (send/buy)" table.
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