On Thu, Feb 24, 2011 at 8:02 PM, David Johnston <polobo@yahoo.com> wrote:
> A column constraint can only reference its own column. Since you are
> referencing "completed" in the CHECK it implicitly converts the Column
> constraint into a Table constraint - and table constraints do not reference
> the name of a column like a column constraint does during name
> auto-generation.
Oh ok, that's a good explanation, thank you
>
> # alter table pref_match add column win integer default 0 check (completed
>>= win and win >= 0);
>
> Now I have:
>
> # \d pref_match
> Table "public.pref_match"
> Column | Type | Modifiers
> -----------+-----------------------+------------------------------------
> -----------+-----------------------+-----
> id | character varying(32) |
> started | integer | default 0
> completed | integer | default 0
> quit | integer | default 0
> yw | character(7) | default to_char(now(), 'IYYY-IW'::text)
> win | integer | default 0
> Check constraints:
> "pref_match_check" CHECK (completed >= win AND win >= 0)
> "pref_match_completed_check" CHECK (completed >= 0)
> "pref_match_quit_check" CHECK (quit >= 0)
> "pref_match_started_check" CHECK (started >= 0) Foreign-key constraints:
> "pref_match_id_fkey" FOREIGN KEY (id) REFERENCES pref_users(id)
>
