Addition in SQL using SELECT SUM command

SQL

The SELECT SUM statement is like a virtual calculator for our database, allowing us to effortlessly calculate the total of values in a specific column.

Syntax

The basic syntax of the SELECT SUM statement is as follows:

SELECT SUM(column_name) AS total_sum
FROM table_name;

column_name: The name of the column for which you want to calculate the sum.
total_sum: An alias assigned to the result of the SUM operation for better readability.

Database Table: `sales`

order_id	product_name	sales_amount	order_date
1	Laptop	1200	2023-01-15
2	Smartphone	800	2023-02-03
3	Headphones	150	2023-02-10
4	Laptop	1000	2023-03-05
5	Smartphone	900	2023-03-18

Now, let’s use this table for the examples in the tutorial.

Basic Example

Let’s use the SUM function to calculate the total sales amount from the “sales” table:

SELECT SUM(sales_amount) AS total_sales
FROM sales;

Output

sales_amount
4050

Let’s explore additional examples using the “sales” database to showcase the versatility of the SQL SELECT SUM command.

Example 1: Total Sales for Each Product Category

Suppose you want to know the total sales for each product category. You can use the GROUP BY clause to achieve this:

SELECT product_category, SUM(sales_amount) AS total_sales
FROM sales
GROUP BY product_category;

product_category	total_sales
Electronics	3050
Accessories	150

This query groups the sales data by product category, providing a clear breakdown of total sales for each category.

Example 2: Monthly Sales Totals

If you want to analyze sales on a monthly basis, you can extract the month from the order_date and calculate the total sales for each month:

SELECT EXTRACT(MONTH FROM order_date) AS month, SUM(sales_amount) AS total_sales
FROM sales
GROUP BY month;

month	total_sales
1	1200
2	950
3	1900

Here, the query extracts the month from the order_date and presents the total sales for each month.

Example 3: Combined Aggregation with AVG and COUNT

You can combine multiple aggregation functions in a single query. For instance, finding the average sales and the number of orders for each product:

SELECT product_name, AVG(sales_amount) AS average_sales, COUNT(order_id) AS order_count
FROM sales
GROUP BY product_name;

product_name	average_sales	order_count
Laptop	1100	2
Smartphone	850	2
Headphones	150	1

This query showcases the combined use of AVG and COUNT along with the SELECT SUM command for a comprehensive analysis.