mysql aggregate functions (2)

Average svg

  select avg(sal + IFNULL(comm,0)) as avg_sal from t_emp

The total sum

select sum(sal + IFNULL(comm,0)) as sum_sal from t_emp 

The maximum max

select max(sal + IFNULL(comm,0)) as max_sal from t_emp 

The minimum min

select min(sal + IFNULL(comm,0)) as min_sal from t_emp 

Total count

select count(*) as cout from t_emp 

 

Grouping queries

select deptno, avg(sal) from t_emp
GROUP BY deptno