2006-10-04 00:47:40 · 2 answers · asked by benam 1 in Computers & Internet ➔ Other - Computers
bhudhu
2006-10-04 01:06:05 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Do you mean Referential Integrity ? Simply put, it is like this.
Suppose you have a table, COURSE-MASTER, where all course details are stored; e.g., E001 for English Literature, E002 for English Grammar, M001 for Mathematics Algebra, M002 for Mathematics Trigonometry, etc. Assume that no course is offered for Philosophy.
Suppose you have another table, COURSE-REGISTRATION, where registration details for the various courses are stored. Referential Integrity would make sure that there are no course code values in this table that do not exist in COURSE-MASTER table. This means while students can register for courses like E001, E002, M001, M002, etc., no registration is possible for Philosophy.
Of course there are formal definitions of Referential Integrity which I am avoiding here.
2006-10-04 01:14:25 · answer #2 · answered by Anonymous · 0⤊ 0⤋