Re: Doubt on query

On Sep 25, 2008, at 4:59 PM, x asasaxax wrote:

> Hi everyone,
>
> I have this table:
>
> create table cat(
> cod integer,
> cod_super integer,
> constraint cod_super_fk Foreign Key(cod_super) references cat(cod),
> constraint cod_pk Primary Key(cod)
> );
>
> insert into cat values(0, 1);
> insert into cat values(1, 0);
> insert into cat values(2, 0);
> insert into cat values(3, 2);
> insert into cat values(4, 3);
> insert into cat values(5, 4);
> insert into cat values(6, 0);
> insert into cat values(7, 0);
>
>
> The Query i want to do is:
> I want to know all the children´s and subchildrens.
> Example 1: I want to know the children´s of 0 will return 1, 2, 3,
> 4, 5, 6, 7
> Example 2: I want to know the children´s of 1 will return nothing
> Example 3: I want to know the children´s of 2 will return 3, 4, 5
>
>
> Did anyone knows how can i do this query?
>
> Thanks a lot
> :)
>

Read this, it might shine a light for a other method of doing this.

http://www.ibase.ru/devinfo/DBMSTrees/sqltrees.html

Ries