The LN function returns the natural log value (base = e) of an antilogarithm x. The return value is a DOUBLE type. If the antilogarithm is 0 or a negative number, an error is returned.
LN ( x )
SELECT ln(1), ln(2.72);
ln(1) ln(2.72)
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0.000000000000000e+00 1.000631880307906e+00