The SQL COUNT(), AVG() and SUM() Functions
The COUNT() function returns the number of rows that matches a specified criteria.
The AVG() function returns the average value of a numeric column.
The SUM() function returns the total sum of a numeric column.
COUNT() Syntax
SELECT COUNT(column_name)
FROM table_name
WHERE condition;
AVG() Syntax
SELECT AVG(column_name)
FROM table_name
WHERE condition;
SUM() Syntax
SELECT SUM(column_name)
FROM table_name
WHERE condition;