Prev Next

PostgreSQL SUM

The SUM() function calculates the total of numeric values in a specified column. It’s often combined with GROUP BY to get subtotals.

Key Topics

1. Basic Syntax

Compute the total for a column:

SELECT SUM(salary) AS total_salary
FROM employees;

2. Using GROUP BY

Calculate totals per group (e.g., department):

SELECT department, SUM(salary) AS dept_total
FROM employees
GROUP BY department;

Each department’s salary sum is shown separately.

Best Practices

  • Ensure the column is a numeric type suitable for summation (e.g., INT, DECIMAL).
  • Use GROUP BY for aggregated sums by categories.

Key Takeaways

  • SUM() returns the total of numeric values.
  • Combine with GROUP BY to compute category-wise totals.
Prev Next