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Question 106Asked in DSSSB PGT Computer Science (Technical), 11 Jul 2021

Which of the following statement(s) is/are correct regarding COUNT functions in Structured Query Language of Relational Database Management System?

Which of the following statement(s) is/are correct regarding COUNT functions in Structured Query Language of Relational Database Management System? I. COUNT(*) is used to count the number of values in a column. II. COUNT() is used to count the number of rows of the query result.
  1. AOnly I
  2. BOnly II
  3. CBoth I and II
  4. DNeither I nor II
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Correct answer: (D) Neither I nor II

Explanation

Both statements are reversed: COUNT(*) counts all rows of the result, while COUNT(column) counts the non-NULL values in a column. So neither is correct.

From DSSSB PGT Computer Science PYQ (Technical), 11 Jul 2021

This is question 106 of DSSSB PGT Computer Science PYQ (Technical), 11 Jul 2021. See all questions of this paper with answers, or attempt the paper as a timed online test to get your score and all-India rank.