LOG2 Function in SQL

The LOG2 function returns the base-2 logarithm of a given number.

? Syntax:

LOG2(number)

• number: A positive numeric value.

? Example:

SELECT LOG2(8) AS base2_log;

Result:

Because 2³ = 8

? Notes:

• The input must be greater than 0.

• Returns NULL or an error if the input is 0 or negative.

• Supported in:

  • ? MySQL

  • ? SQL Server (not directly supported; use: LOG(number) / LOG(2))

  • ? Oracle (use: LOG(2, number) or LN(number)/LN(2))

?? SQL Server Equivalent:

SELECT LOG(8) / LOG(2) AS base2_log;

?? Oracle Equivalent:

SELECT LOG(2, 8) AS base2_log FROM dual;-- orSELECT LN(8) / LN(2) AS base2_log FROM dual;

Let me know if you'd like a comparison table of LOG, LOG2, LOG10, and LN across databases!