Multiple choice technology databases

select level from dual connect by level between 1 and 50 minus select level from dual connect by level between 2 and 50; o/p:

  1. 1

  2. No rows returned

  3. Values 1 to 50

  4. Values 0 & 1

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Both hierarchical queries generate the same sequence of numbers from 1 to 50. Subtracting the second result set from the first using MINUS results in an empty set, yielding no rows returned.