Aggregate Functions in MySQL

 SUM, COUNT, MIN, MAX, AVG AND STRING FUNCTIONS - UCASE, FORMAT

                             CONCAT,CHAR_LENGTH and LEFT FUNCTIONS 

SELECT count(*) from employee; -- Here we use COUNT how many employee

If we need count of Manager

SELECT count(*) Manager

FROM employee

WHERE job_Desc ="Manager";

-- Average function

SELECT avg(salary)

FROM employee

WHERE Job_Desc ="manager";

 

-- SUM function

select sum(salary)

from employee

where Job_Desc="Analyst";

 

-- MAX and MIN function

select MAX(SALARY)

from employee;

 

select MIN(SALARY)

from employee;

 

-- STRING

-- UCASE function for UPPER CASE

select  ucase(ename) Name,salary   --- Here we used Alias name

from employee;

 

-- We can count the character in Name column for that Char_Length function

select ename,char_length(ename) No_Character

from employee;

 

-- Here we use CONCAT function ,CONCAT mean join 

/* Here before the salary i want RS so using CONCAT function */

select ename,concat('Rs.',salary) Salary

from employee;

 

-- FORMAT function

/* Here FORMAT function used to separate the digit and that 0 for decimal values */

select ename,concat('Rs.',format(salary,0)) Salary 

from employee;

 

-- LEFT function

/* Here i need Job desc first three letter so used LEFT */

select  ename,LEFT(Job_desc,3)

from employee;