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

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

The COUNT() function returns the number of rows that matches a specified criterion.

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;

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