POSC Specifications: Epicentre Version 3.0
Logical Data Model
ENTITY
SCHEDULE_ACTIVITY
SUBTYPE OF
(
association
);
activity :
activity
;
relative_time :
OPTIONAL
ndt_time
;
relative_to :
OPTIONAL
schedule_activity
;
schedule :
schedule
;
scheduled_cost :
OPTIONAL
ndt_money
;
INVERSE
referenced_by :
SET [0:?] OF
schedule_activity
FOR
relative_to;
UNIQUE
si: schedule, activity;
WHERE
mse: EXISTS(relative_to) XOR EXISTS(schedule);
END_ENTITY
; (* schedule_activity *)
Generated on Tue Jul 10 19:39:05 2001
© Copyright 2001 POSC. All rights reserved.