In SQL, there are two built-in functions to sum or average the data in your table.

In this article I will show you how to use the ** SUM **and

**functions in SQL using code examples.**

`AVG`

## How to use the SUM function in SQL

If you need to add a group of numbers in your table you can use the `SUM`

function in SQL.

This is the basic syntax:

`SELECT SUM(column_name) FROM table_name;`

The `SELECT`

statement in SQL tells the computer to get data from the table.

The `FROM`

clause in SQL specifies which table we want to list.

In this example, we have a table called `students`

with the columns of `id`

, `name`

, `date`

, and `total`

. We want to add up the total number of candy bars sold by all of the students.

We can use this syntax to get the total number of candy bars sold:

```
SELECT SUM(total) FROM students;
```

The result would be 41.

We can also get the sum for each student using the `GROUP BY`

clause.

The first part is to select the name and sum for the total number of candy bars sold, like this:

`SELECT name, SUM(total)`

The second part is to group the sum by name:

`FROM students GROUP BY name;`

Here is the complete code to group the total number of candy bars sold by student name.

```
SELECT name, SUM(total) FROM students GROUP BY name;
```

This is what the result would look like in our table:

Right now the results are grouped alphabetically by student name.

We can modify the code to sort the list of results from largest total to smallest using the `ORDER BY`

clause.

`SELECT name, SUM(total) FROM students GROUP BY name ORDER BY total DESC;`

The `DESC`

keyword tells the computer to sort from largest to smallest total.

If we wanted to sort the total from smallest to largest, then we would omit the `DESC`

keyword.

```
SELECT name, SUM(total) FROM students GROUP BY name ORDER BY total;
```

## How to use the AVG function in SQL

The `AVG`

function finds the arithmetic mean for a group of records in a SQL table. An average, or arithmetic mean, is the sum of a group of numbers divided by the count for that group.

For example, 2+4+4+6+6+8 is 30 divided 6 which results in an average of 5.

This is the basic syntax for the `AVG`

function:

```
SELECT AVG(column_name) FROM table_name;
```

In this example, we have a table called `students`

, with columns of `id`

, `name`

, `date`

, and `scores`

. We want to find the average of all the students' test scores in our table.

We have to use this syntax to get the average for the test scores:

`SELECT AVG(scores) FROM students; `

The average would be 85.333.

We can also use the `ROUND`

function to round our result to the nearest integer.

`SELECT ROUND(AVG(scores)) FROM students; `

We can also get the average for each student using the `GROUP BY`

clause.

The first part is to select the name and average for the scores, like this:

`SELECT name, ROUND(AVG(scores))`

The second part is to group the average scores by name:

`FROM students GROUP BY name;`

This is what the code looks like all together:

`SELECT name, ROUND(AVG(scores)) FROM students GROUP BY name;`

This is what the result looks like in the table:

## Conclusion

There may be times were you need to find the sum or average of records in your table.

If you need to add a group of numbers in your table you can use the `SUM`

function in SQL.

This is the basic syntax:

`SELECT SUM(column_name) FROM table_name;`

If you need to arrange the data into groups, then you can use the `GROUP BY`

clause.

The `AVG`

function finds the arithmetic mean for a group of records in a SQL table. An average, or arithmetic mean, is the sum of a group of numbers divided by the count for that group.

This is the basic syntax.

```
SELECT AVG(column_name) FROM table_name;
```

I hope you enjoyed this tutorial and best of luck on your SQL journey.