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Enrolment was split - SQL
Example shows how relvars IS_CALLED and IS_ENROLLED_ON can be derived from the original ENROLMENT relvar, using projection in the initial assignment to those relvars. Here is how the same effect can be achieved in SQL:
Example: Splitting ENROLMENT
CREATE TABLE IS_CALLED
AS (SELECT DISTINCT StudentId, Name FROM ENROLMENT)
WITH DATA;
ALTER TABLE IS_CALLED ADD CONSTRAINT PRIMARY KEY ( StudentId );
CREATE TABLE IS_ENROLLED_ON
AS (SELECT DISTINCT StudentId, CourseId FROM ENROLMENT)
ALTER TABLE ADD CONSTRAINT PRIMARY KEY ( StudentId, CourseId ) ;
DROP TABLE ENROLMENT;
Explanation:
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