Question

Which of the following functions does an iterator not provide

(a) Open()

(b) Next()

(c) Close()

(d) Wait()

I had been asked this question in a job interview.

The question is from Evaluation of Expressions topic in division Query Processing and Optimization of RDBMS

Answer 1

The correct answer is (d) Wait()

Explanation: The iterator does not provide the wait() function but it provides open(), next() and close() operations.