Andreas Joseph Krogh wrote:
Hi all!
Is there a simple way to add a "NOT NULL constraint" to a column without using
a trigger if another column is not null?
Something like this:
CREATE TABLE activity(
id SERIAL primary key,
name varchar not null,
created timestamp not null default now(),
modified timestamp,
created_by integer not null,
modified_by integer
);
alter table activity alter column modified_by set not null where modified is
not null;
I want a constraint which says: "modified_by not null if modified is not
null".
Would a CHECK do? Something like:
ALTER TABLE activity ADD CONSTRAINT both_modified_set CHECK
((modified_by IS NULL AND modified IS NULL) OR (modified_by IS NOT NULL
AND modified IS NOT NULL))
--
Richard Huxton
Archonet Ltd
---------------------------(end of broadcast)---------------------------
TIP 4: Have you searched our list archives?
http://archives.postgresql.org
