# MySQL INTERVAL Operator

The MySQL Interval Operator uses the binary search method to search the items and returns the values from 0 to N. In this article, we show how to use the MySQL Interval Operator with multiple examples.

## MySQL Interval Operator Syntax

The basic syntax of the interval in MySQL is:

`SELECT INTERVAL (N, N1, N2, N3,....Nn) `

If N < N1, then 0 is returned. N < N2 means 1, N < N3 means 2 etc. This Interval function requires the arguments in ascending order. I mean, N1 < N2 < N3 < N4…….< Nn. Otherwise, it won’t work.

## MySQL Interval Example

In this example, we are using the same values from N1 to N7. However, we are changing the N values to check the interval position.

`SELECT INTERVAL(45, 10, 20, 30, 40, 50, 60, 70);SELECT INTERVAL(11, 10, 20, 30, 40, 50, 60, 70);SELECT INTERVAL(67, 10, 20, 30, 40, 50, 60, 70);`

Within the first statement, we used the N value less than N1 so, it returned 0. Next, we used the N Value greater than N7 so, 7 has returned. Within the third statement, we used NULL as N. This is the reason, MySQL has returned -1.

`SELECT INTERVAL(6, 10, 20, 30, 40, 50, 60, 70);SELECT INTERVAL(98, 10, 20, 30, 40, 50, 60, 70);SELECT INTERVAL(NULL, 10, 20, 30, 40, 50, 60, 70);`

### MySQL Interval Operator Example 2

The following query finds the interval position of a Customer based on the value 76000. First, 76000 act as N and employee income as N1. Next, Income acts as N and 76000 as N1.

Here, we used Order By clause to sort the Income in ascending order; otherwise, the Interval function won’t work.

`SELECT EmpID,        `First Name`,       `Last Name`,       Qualification,       Occupation,       Income,       INTERVAL(76000, Income) AS Res1,       INTERVAL(Income, 76000) AS Res2,       Sales FROM `MySQL Tutorial`.customer ORDER BY Income ASC;`