MySQL SUM Function: Sum

The SUM() function in MySQL is used to return the summed value of an expression. Typically, it's used to add up numeric column values in a table.

The basic syntax of the SUM() function is:

SUM(expression)

The expression can be a column name, the result of another function, or a math operation.

Please note that the SUM() function only includes non-NULL values. If all values are NULL, the SUM() function returns NULL.

Here's an example. Let's say we have a sales table with the following data:

id	product	amount
1	A	10
2	B	20
3	A	30
4	C	40

We could use the SUM() function to find the total amount of all sales:

SELECT SUM(amount) AS total_sales FROM sales;

This would return 100, which is the sum of all values in the amount column.

We could also use SUM() in combination with the GROUP BY statement to find the total sales for each product:

SELECT product, SUM(amount) AS product_sales 
FROM sales 
GROUP BY product;

This would return:

product	product_sales
A	40
B	20
C	40

This shows the total sales for each product in the sales table.

Keep in mind that SUM() is an aggregate function, meaning it returns a single result value. It's often used in conjunction with GROUP BY to aggregate results by certain columns.

Using SUM function in MySQL for total aggregation:
- Utilize the SUM function in MySQL for aggregating and calculating the total sum of a column's values.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```
MySQL SUM function example:
- An example of using the SUM function in MySQL to calculate the total sum of values.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```
How to sum values in MySQL:
- Sum values in MySQL using the SUM function, specifying the column or expression to be summed.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```
Aggregate functions in MySQL: SUM usage:
- Incorporate the SUM function as one of the aggregate functions in MySQL for total aggregation.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```
MySQL summing values with SUM:
- Sum values in MySQL by using the SUM function to calculate the total sum.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```
Summation operations in MySQL using SUM:
- Perform summation operations in MySQL using the SUM function for calculating totals.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```
Totaling values with SUM in MySQL:
- Calculate the total sum of values in MySQL using the SUM function.
```
SELECT SUM(column1) AS total_sum FROM my_table;
```