How to Find the Minimum Value of a Column in SQL

Problem:

You’d like to find the smallest numeric value in a column.

Example:

Our database has a table named employment with data in the following columns: id, first_name, last_name, department, and salary.

Let’s find the lowest salary among all employees.

Solution:

SELECT MIN(salary) as min_salary
FROM employment;

Here’s the result:

Discussion:

To find the minimum value of a column, use the MIN() aggregate function; it takes as its argument the name of the column for which you want to find the minimum value. If you have not specified any other columns in the SELECT clause, the minimum will be calculated for all records in the table. In our example, the query returns the minimum salary among all employees.

Of course, since it’s an aggregate function, MIN() can also be used with groups. For example, if we’d like to find the minimum salary for each department, we can write this query:

SELECT department, MIN(salary) as min_salary
FROM employment
GROUP BY department;

This query returns the minimum salary for each department: