PostgreSQL/Math Functions/ln

ln(dp or numeric) natural logarithm

postgres=#
postgres=# -- ln(dp or numeric) natural logarithm
postgres=#
postgres=# select ln(2.0);
         ln
--------------------
 0.6931471805599453
(1 row)
postgres=#

ln(exp(10.0))

postgres=#
postgres=# SELECT ln(exp(10.0)) AS inverse_example;
   inverse_example
---------------------
 10.0000000000000000
(1 row)
postgres=#

ln(x): Returns the natural logarithm of x (the inverse of the exp() function)

postgres=#
postgres=# -- ln(x): Returns the natural logarithm of x (the inverse of the exp() function)
postgres=#
postgres=# SELECT ln(10.0) AS natural_log;
    natural_log
--------------------
 2.3025850929940457
(1 row)
postgres=#