SQL MAX() function

The MAX() function is an aggregate function that is used to find the largest value in the given column or expression. It can be applied on the numeric, character, or date values.

Syntax:

SELECT MAX(column_name)
FROM table_name
[WHERE condition]
[GROUP BY];

For the demo purpose, we will use the following Employee and Department tables in all examples.

The following selects the maximum salary from the Employee table.

SELECT MAX(Salary) AS "Highest Salary" FROM Employees;

The following query gets all employees whose salary is maximum.

SELECT * FROM Employee 
WHERE Salary = (SELECT MAX(Salary) FROM Employee);

The MAX() is an aggregate function, so it can be used in Group By queries. The following query gets highest salary in each department.

SELECT DeptId, MAX(Salary) AS "Highest Salary" 
FROM Employee
GROUP BY DeptId;

The MAX() function can be allpied on the varchar columns. The following selects the largest FirstName from the Employee table.

SELECT MAX(FirstName) AS "Largest FirstName" FROM Employee;