Multiple choice technology databases

select rownum from dual;

  1. It will show one row but no no column,no value-,not even NULL value

  2. NULL

  3. 0

  4. 1
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

ROWNUM is a pseudo-column that assigns a number to each row returned. DUAL has one row, so ROWNUM=1 for that row. The query returns 1.

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