SUM()

SUM() is a SQL function in the Aggregate Functions category. Returns the sum of all non-NULL values in a group. Works with numeric columns. The syntax is SUM(expression). It accepts expression — numeric column. It returns numeric sum. A typical example: SELECT SUM(salary) FROM employees; -- Total salary cost SELECT SUM(salary) FROM employees WHERE department = 'IT'; A close relative is COUNT(), which returns the number of rows (or non-NULL values) in a group. A close relative is AVG(), which returns the average (mean) of all non-NULL values in a group. A close relative is MIN(), which returns the minimum value from a group. More about this category: Aggregation functions — COUNT, SUM, AVG, MIN, MAX, GROUP BY, HAVING. Related Aggregate Functions entries: COUNT(), AVG(), MIN(), MAX(), GROUP_CONCAT() / LISTAGG(), STRING_AGG(), VARIANCE() / VAR_SAMP(), STDDEV() / STDDEV_SAMP(). This page is part of the free SQL Reference documentation covering 762+ statements, functions, and clauses, each with syntax, parameters, return values, and examples for MySQL, PostgreSQL, SQL Server, and SQLite.