LOG10() function

SELECT LOG10( X )

SELECT LOG10(3); // Output is 0.477121254719662
SELECT LOG10(0.1); // Output is -1
SELECT LOG10(0); // Output is NULL

Using ROUND() with LOG()

SELECT ROUND(LOG10(2),2);// Ouput is 0.30
SELECT ROUND(LOG10(-2),2); // Ouput is NULL
SELECT ROUND(LOG10(7),2); // Output is 0.85