| From: | "Jeffrey W(dot) Baker" <jwbaker(at)acm(dot)org> | 
|---|---|
| To: | Joost Kraaijeveld <J(dot)Kraaijeveld(at)Askesis(dot)nl> | 
| Cc: | Postgres general mailing list <pgsql-general(at)postgresql(dot)org> | 
| Subject: | Re: Howto retrieve all the grandchildren of all the | 
| Date: | 2002-01-25 23:48:20 | 
| Message-ID: | 1012002501.2700.15.camel@heat | 
| Views: | Whole Thread | Raw Message | Download mbox | Resend email | 
| Thread: | |
| Lists: | pgsql-general | 
On Fri, 2002-01-25 at 15:13, Joost Kraaijeveld wrote:
> I have three tables. Table 1 contains the root of a tree. Table 2 contains
> the children of table 1 (column acting as foreign key). Table 3 contains the
> children of table 2 (column acting as foreign key). Basically it contains a
> three level n-ary tree.
> 
> Is it possible to retrieve the grandchildren if I have the primary key of a
> record in table 1, assuming that each table has a primary key and an
> appropriate foreign key, and if so, what should be the SQL syntax to do so?
SELECT table3.*
  FROM table3
     , table2
     , table1
 WHERE table3.parent = table2.id
   AND table2.parent = table1.id
   AND table1.id = 123456
-jwb
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Jeffrey W. Baker | 2002-01-26 00:21:28 | Re: Howto retrieve all the grandchildren of all the | 
| Previous Message | Joost Kraaijeveld | 2002-01-25 23:13:39 | Howto retrieve all the grandchildren of all the children |