Function in SQL

Firstly, we create a table with name employee

SQL AVG() Function -

This function returns the average value of numeric column in table

Example –

select avg(salary) as AverageSal from employee

output - 

SQL count function –

The COUNT() returns number of rows from the table

Example –

select COUNT(*) as ROWS from employee

Output – ROWS - 3 

SQL Max() Function –

This function returns the largest value of the selected column

Example –

select MAX(salary) as HigherSal from employee

Output – HigherSal – 24000

SQL Min() Function –

This function returns the smallest value from the column

Example –

select MIN(salary) as MinSal from employee

Output – MinSal -15000

 

SQL SUM() Function –

SUM() function returns the total of any column

Example –

select SUM(salary) as TotalSal from employee

Output – 59000

SQL LEN() function –

This function returns the number of character of any column

Example –

select LEN(name) as Name from employee

Output – 

 

SQL ROUND() function -

This is used to round a numeric field to the number of decimals specified.

Syntax-

Select round(column_name,decimals) from table-name