The MySQL `ROUND()`

function is used to round a decimal number to the nearest integer (whole) number.

When the decimal value is `.5`

or higher, the function will round your number up.

When the decimal value is lower than `.5`

then the function will round your number down.

Here’s an example of the `ROUND()`

function in action:

```
SELECT ROUND(7.5), ROUND(7.499);
```

The output of the query above will be as follows. Notice how `7.5`

rounds up to `8`

while `7.499`

rounds down to `7`

:

```
+------------+--------------+
| ROUND(7.5) | ROUND(7.499) |
+------------+--------------+
| 8 | 7 |
+------------+--------------+
```

The `ROUND()`

function can round both a positive number and a negative number.

When you pass a negative number to the function, then the number will be rounded down when the decimal place is higher than `.5`

as shown below:

```
mysql> SELECT ROUND(-7.5), ROUND(-7.499);
+-------------+---------------+
| ROUND(-7.5) | ROUND(-7.499) |
+-------------+---------------+
| -8 | -7 |
+-------------+---------------+
```

The full syntax of the `ROUND()`

function is as shown below:

```
ROUND(number, decimals);
```

The `ROUND()`

function accepts two arguments:

- The
`number`

to round as the first parameter - And the number of
`decimal places`

to round the number to

If you omit the `decimal places`

, then the specified `number`

will be rounded to zero decimal places (integer or whole number)

When the decimal places of your number are less than the specified `decimals`

argument, then the function will do nothing to the given number.

Take a look at the following example. Notice how the first two numbers are unchanged by the function:

```
mysql> SELECT ROUND(7.5, 2), ROUND(7.49, 2), ROUND(7.299, 2);
+---------------+----------------+-----------------+
| ROUND(7.5, 2) | ROUND(7.49, 2) | ROUND(7.299, 2) |
+---------------+----------------+-----------------+
| 7.5 | 7.49 | 7.30 |
+---------------+----------------+-----------------+
```

Finally, you can pass the name of your MySQL table column to the function to round the numbers stored in that column.

To show you what I mean, imagine you have a `scores`

table in your MySQL database with the following data:

```
mysql> SELECT * FROM scores;
+----+-------+-------+
| id | name | score |
+----+-------+-------+
| 1 | Jack | 4.9 |
| 2 | Susan | 7.4 |
| 3 | Mark | 6.73 |
| 4 | Fany | 9.15 |
+----+-------+-------+
```

When you need to round the `score`

column values, then you can pass the `score`

column as the first argument to the `ROUND()`

function in your SQL query.

The following example query:

```
SELECT name, score, ROUND(score) AS `rounded score` FROM scores;
```

Will produce the following result:

```
+-------+-------+---------------+
| name | score | rounded score |
+-------+-------+---------------+
| Jack | 4.9 | 5 |
| Susan | 7.4 | 7 |
| Mark | 6.73 | 7 |
| Fany | 9.15 | 9 |
+-------+-------+---------------+
```

The rounded value of each `score`

value is returned next to the original number.

And that’s how the MySQL `ROUND()`

function works. You can round any floating or decimal numbers using the function.

Feel free to use any MySQL query provided in this tutorial 😉