Given an employees table as follows: empid name managerid a1 bob NULL b1 jim a1 B2 tom a1 What value will select count(*) from employees return?

Question

Multiple choice sql

Given an employees table as follows: empid name managerid a1 bob NULL b1 jim a1 B2 tom a1 What value will select count(*) from employees return?

1
2
3

Reveal answer Fill a bubble to check yourself

C Correct answer

Explanation

COUNT(*) returns the total number of rows. The table has 3 rows (a1 bob NULL, b1 jim a1, B2 tom a1), so the answer is 3.

AI explanation

AI 1

To determine the value that will be returned by the query select count(*) from employees, let's analyze the given employees table:

empid | name | managerid
------------------------
a1    | bob  | NULL
b1    | jim  | a1
B2    | tom  | a1

The query select count(*) from employees counts the number of rows in the employees table. It does not consider NULL values.

In this case, there are three rows in the table: (a1, bob, NULL), (b1, jim, a1), and (B2, tom, a1). Therefore, the query will return a value of 3.

Therefore, the correct answer is C) 3.

Answer 1

none of the above

Given an employees table as follows: empid name managerid a1 bob NULL b1 jim a1 B2 tom a1 What value will select count(*) from employees return?

Keep practicing — related questions