Oracle 9.
Trying to put a constraint. The date_time field in table Visit should
be >= than date_admitted field in table Admission.
CREATE TABLE Visit (
adid INT REFERENCES myAdmission(adi d),
date_time DATE CONSTRAINT date_time_limit s
CHECK (date_time >= ALL
(SELECT date_admitted
FROM Admission, Visit
WHERE Admission.adid = Visit.adid)),
);
I get subquery not allowed here. I don't have much experience, but as
far as i can tell from my book this should work. But then again I just
learned that oracle does not allow ASSERTION which is taught in this
book; so is this the same problem? If yes could someone tell me how to
get around this please.
Trying to put a constraint. The date_time field in table Visit should
be >= than date_admitted field in table Admission.
CREATE TABLE Visit (
adid INT REFERENCES myAdmission(adi d),
date_time DATE CONSTRAINT date_time_limit s
CHECK (date_time >= ALL
(SELECT date_admitted
FROM Admission, Visit
WHERE Admission.adid = Visit.adid)),
);
I get subquery not allowed here. I don't have much experience, but as
far as i can tell from my book this should work. But then again I just
learned that oracle does not allow ASSERTION which is taught in this
book; so is this the same problem? If yes could someone tell me how to
get around this please.