Purpose
You can call this function to return the logarithm of numeric_expression to base e.
Note
eis a mathematical constant equal to 2.71828183....
Syntax
LN (numeric_expression)
Parameters
numeric_expression is of a numeric data type whose value is greater than 0, such as NUMBER, FLOAT, BINARY_FLOAT, or BINARY_DOUBLE, or is of any data type that can be implicitly converted to a numeric data type.
Return type
When the parameter is of the BINARY_FLOAT data type, the return type is BINARY_DOUBLE. Otherwise, the return type is the same as the data type of numeric_expression.
Examples
The following example returns the natural logarithm of 9.
obclient> SELECT LN(9) FROM DUAL;
+------------------------------------------+
LN(9)
+------------------------------------------+
2.19722457733621938279049047384505140929
+------------------------------------------+
1 row in set