Question

What MySQL COUNT() function returns if there are some NULL values stored in a column also?

Answer 1

Answer:

number of rows present in table including rows which has NULL values

Explanation:

if there is a table called A and has column srno,Name,Age

----------------------------------------------------------------------------

srno      Name       Age

-----------------------------------------------------------------------------

1          Abhay         25

2         Chetan        20

3          NULL          NULL

4         Harshal        NULL

Then

select count(*) from A will return 4

select count(Name) from A will return 3

select count(Age) from A will return 2

select count(srno) from A will return 4