SQL SUM

Understanding SQL SUM Function

The SQL SUM function aggregates and calculates the total sum of a specified numeric field or formula within a dataset. Its syntax is simple yet powerful.

SELECT SUM(expression)
FROM tables
WHERE conditions;

The 'expression' can be a numerical field or a formula, allowing for flexible application.

SQL SUM in Action

Let's go through real-world examples to understand the core concept of the SQL SUM function.

We need to find the total salary of employees earning over $10,000 per month. The query would be something like this:

SELECT SUM(salary) AS "Total Salary"
FROM employee_details
WHERE salary > 120000;

This demonstrates the function's simplicity and efficiency in handling real-world scenarios.

Distinct Values with SQL SUM

The SQL DISTINCT clause can be combined with the SQL SUM function to calculate the total salary for distinct values above $10,000.

SELECT SUM(DISTINCT salary) AS "Total Salary"
FROM employee_details
WHERE salary > 10000;

This opens up new possibilities in data analysis and presentation

Grouping Data with SQL SUM

To perform a detailed analysis, we can utilize the SQL GROUP BY statement. This allows us to determine the total sales for each department.

SELECT department, SUM(sales) AS "Total Sales"
FROM order_details
GROUP BY department;

The SQL SUM function is versatile in handling grouped data, offering a comprehensive view of department-wise sales.

This command instructs SQL to count the number of entries in the specified column_name within the table_name.