SQLite ln() Function

In SQLite, the ln() function returns the natural logarithm of a number.

Syntax

ln(x)Code language: SQL (Structured Query Language) (sql)

Arguments

x is the number you want to calculate the natural logarithm. x can be a literal number, an expression, or a table column.

Return type

real

The ln(x) returns the natural logarithm of x with the real type. If x is NULL, the ln() function returns NULL.

If x is a string, the ln() will attempt to convert it to a number before calculating the natural logarithm. If it cannot convert x to a number, it’ll return NULL.

Examples

The following example uses the ln() function to calculate the natural logarithm of 1:

SELECT ln(1);Code language: SQL (Structured Query Language) (sql)

Output:

ln(1)
-----
0.0Code language: SQL (Structured Query Language) (sql)

The following example uses the ln() function to compute the natural logarithm of e:

SELECT ln(exp(1)) result;Code language: SQL (Structured Query Language) (sql)

Output:

result
------
1.0Code language: SQL (Structured Query Language) (sql)

In this example, exp(1) returns e, therefore the natural logarithm of e is 1.

The following example uses the ln() function to calculate the natural logarithm of NULL:

SELECT ln(NULL) result;Code language: SQL (Structured Query Language) (sql)

Output:

result
------
NULLCode language: SQL (Structured Query Language) (sql)

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