Re: ALTER TABLE

* Martins Zarins <mark(at)vestnesis(dot)lv> [05.06.2003 10:18]:
> Hello!
> Can someone explain me, why last ALTER fails?
>
> work=# \d rdu
> Table "rdu"
> Column | Type | Modifiers
> -------------+-----------------------------+------------------------------------------------
> id | integer | not null default
> nextval('"rdu_id_seq"'::text)
> numurs | integer |
> versija | integer |
> klients_id | integer |
> pasutitajs | text |
> agents_id | integer |
> pasut_nr | integer |
> status_id | character varying(1) | default 'S'
> start_time | timestamp without time zone | not null default now()
> end_time | timestamp without time zone |
> finish_time | timestamp without time zone |
> apraksts | text |
> Indexes: rdu_agents_id,
> rdu_klients_id
> Unique keys: rdu_id_key
> Triggers: RI_ConstraintTrigger_1187649,
> RI_ConstraintTrigger_1187655,
> RI_ConstraintTrigger_1187673,
> RI_ConstraintTrigger_1187675
>
> work=# ALTER TABLE rdu ADD CONSTRAINT rdu_end_time CHECK ((start_time <=
> end_time) OR end_time IS NULL);
> ALTER
> work=# ALTER TABLE rdu ADD CONSTRAINT rdu_finish_time CHECK ((start_time <=
> finish_time) OR finish_time IS NULL);
> ERROR: AlterTableAddConstraint: rejected due to CHECK constraint
> rdu_finish_time

Perhaps you have some rows, for which check fails,
i.e. (start_time > finish_time AND finish_time IS NOT NULL) is true.

--

Victor Yegorov