LOG

Returns the natural logarithm value of a numeric expression

The natural logarithm is also known as ln or logarithm to the base of the mathematical constant e.

See also LOG10.

Syntax

LOG( expr )

Arguments

Parameter

Description

expr

Positive numeric expression

Returns

When using the LOG floating point number scalar function, real arguments are automatically cast to double precision.

Notes

  • If the input value is NULL, the result is NULL.

Examples

Natural log values

numbers=> SELECT LOG(0.0001), LOG(1), LOG(2.718281), LOG(5000000000000000);
log     | log0 | log1 | log2
--------+------+------+--------
-9.2103 |    0 |    1 | 36.1482