8. BETWEEN & NOT BETWEEN Keywords in SQL

The BETWEEN conditional operator is used to test to see whether or not a value (stated before the keyword BETWEEN) is "between" the two values stated after the keyword BETWEEN.

For example:

SELECT employeeid, age, lastname, salary

FROM employee_info
 
WHERE age BETWEEN 30 AND 40;

This statement will select the employeeid, age, lastname, and salary from the employee_info table where the age is between 30 and 40 (including 30 and 40).

This statement can also be rewritten without the BETWEEN operator:

SELECT employeeid, age, lastname, salary

FROM employee_info

WHERE age >= 30 AND age <= 40;

You can also use NOT BETWEEN to exclude the values between your range.