Strange MySQL AVG() anomaly NULL values

Question

What I\'am doing :

create table sample (id INT(10) PRIMARY KEY AUTO_INCREMENT,name varchar(255),marks INT(10));

insert into sample (name,marks) VALUES(\'sam         


        

Answer 1

Try:

select avg(case marks when null then 0 else marks end) from sample group by name;

Or try and avoid nulls in the table ;)