Re: recursive relationship
Date: 2000/01/12
Message-ID: <85i116$89f$1_at_news1.xs4all.nl>#1/1
> AFAIK, a recursive relationship means that an object of a certain type
> may be related to an object of the same type. Consider the type human,
> spouse is such a relationship (perhaps you have to add "current";-)
>
> CREATE TABLE Human (
> ID INTEGER,
> Name CHAR (255),
> IDSpouse INTEGER);
>
This is a common mistake, this is not real recursion. Real recursive
structures are not possible in a relational database. Examples of real
recursion are chapters/paragraphs of a book (1.1, 1.1.1 and so on) or, very
similar, the DOS path/file-structure (c:, c:\windows\, c:\windows\system and
so on). Try to make a conceptually correct table (or tables if you wish),
and you'll see that it's not possible.
Received on Wed Jan 12 2000 - 00:00:00 CET