Question

Which key accepts multiple NULL values?

(a) Foreign Key

(b) Unique Key

(c) Primary Key

(d) None of the Mentioned

I got this question in an interview for job.

I want to ask this question from Foreign, Candidate, Primary, Composite, Unique Keys in section Planning Oracle Applications of Oracle

Answer 1

Correct choice is (a) Foreign Key

Easy explanation: A foreign key is a key used to link two tables together. This is sometimes called a referencing key.Foreign Key is a column or a combination of columns whose values match a Primary Key in a different table.