Re: Inheritance and Foreign Keys - Mailing list pgsql-general

From Oliver Elphick
Subject Re: Inheritance and Foreign Keys
Date
Msg-id 200101042225.f04MPRH11897@linda.lfix.co.uk
Whole thread Raw
In response to Inheritance and Foreign Keys  (Nelio Alves Pereira Filho <nelio@ifx.com.br>)
List pgsql-general
Nelio Alves Pereira Filho wrote:
  >Here's my situation: I have the following relation
  >
  >table A -----<>------ table B
  >             1:N
  >
  >I created the two tables, and a foreign key from A into B. Now I want to
  >create other tables that inherit from B, but I want that the relation
  >exists for all of them. For that, I created another table, C, that had
  >just one field and inherited from B. No errors showed up, but it didn't
  >complain when I inserted some data into C without the corresponding one
  >in A!!
  >
  >Is it possible to do what I intended?

Unfortunately not.  Inheritance is not properly thought out; at present
it allows fields to be duplicated and records selected from an inheritance
hierarchy, but this is relatively useless because constraints are not
inherited and indexes are not shared.

--
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver
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