SQL COUNT(), AVG() and SUM() Aggregate Functions

SQL COUNT(), AVG() and SUM() Aggregate Functions. The following SQL queries show how to query count, how to query average value, query sum use SQL

SQL COUNT() Syntax:

SELECT COUNT(column)
FROM table_name
WHERE condition;

Example:

SELECT COUNT(id)
FROM employees;

SQL AVG Syntax:

SELECT AVG(column)
FROM table_name
WHERE condition;

Example:

SELECT AVG(salary)
FROM employees;

SQL SUM Syntax:

SELECT SUM(column)
FROM table_name
WHERE condition;

Example:

SELECT SUM(salary)
FROM employees;