sqrt mysql function to get square root of number

SELECT SQRT(16);  -- 4
SELECT SQRT(20);  -- 4.47213595499958

For a negative argument, SQRT() returns NULL.

SELECT SQRT(-25);  -- NULL

Example of sqrt function with update query

We know how to find out hypotenuse of a right angle triangle.
Right triangle showing sides used in the Pythagorean theorem

H² = A² + B²
H = √(A² + B²)

We will create one UPDATE query by using MySQL pow function.
Here it is

UPDATE sql_sqrt
SET H = SQRT(POW(A, 2) + POW(B, 2));

This will update the table with value of hypotenuse . Here is the PHP code to update the table.

require 'config.php'; // Database connection
$query = 'UPDATE sql_sqrt SET H = SQRT(POW(A, 2) + POW(B, 2))';
$stmt = $dbo->prepare($query);
$stmt->execute();
echo 'Successfully updated H';

Download SQL dump file of this table

SQL Math References Standard deviation Average value Query

All Math Functions POW()

Subhendu Mohapatra

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sqrt(): square root of any number

Example of sqrt function with update query

Subhendu Mohapatra