LOG is one of the vital Numeric/Math functions of Oracle. It is used to get the logarithm of x base y. The LOG function is supported in the various versions of the Oracle/PLSQL, including, Oracle 12c, Oracle 11g, Oracle 10g, Oracle 9i and Oracle 8i.
LOG( y, x )
y: It must be a positive number except 1 or 0.
x: It must be a positive number.
The value of base 10 logarithm of 50 is 1.6989700043 and so is the result.