Database Test 4 Computer Subject
Database Test 4 Computer Subject
Question 31
Which one of the following is a set of one or more attributes taken collectively to uniquely identify a record?
A super key is a set of attributes that can uniquely identify a record in a table.
Not clear enough?
Question 32
The subset of a super key is a candidate key under what condition?
A candidate key is a minimal super key, meaning no proper subset of it can uniquely identify a record.
Not clear enough?
Question 33
An attribute in a relation is a foreign key if the _____ key from one relation is used as an attribute in that relation.
A foreign key in one table refers to the primary key in another table to maintain referential integrity.
Not clear enough?
Question 34
Course(course_id, sec_id, semester). Here the course_id, sec_id and semester are _____ and course is a _____?
course_id, sec_id, and semester are attributes (columns) of the relation (table) named course.
Not clear enough?
You might like
How many months were the Israelites on forced labour in Lebanon allowed to spend at home for every month at the labour camp?
| Products | Nigeria | Austria |
|---|---|---|
| Cocoa | 20 tonnes | 12 tonnes |
| Lace | 10 metres | 8 metres |
The opportunity cost ratio for cocoa and lace for Austria and Nigeria is _______