ISNAN

Syntax

ISNAN(number)

Purpose

This function determines whether the value of number is a "Not a Number" (NaN). It returns NULL (true) if the value is NaN, or 0 (false) otherwise.

Examples

1. Enable the ClickHouse extension function mode.

   obclient> ALTER SYSTEM SET sql_func_extension_mode = "ClickHouse";
   

2. Return 0.

   obclient> SELECT ISNAN(1.5);
   

   The return result is as follows:

   +------------+
   | ISNAN(1.5) |
   +------------+
   |          0 |
   +------------+
   1 row in set
   

3. Return NULL.

   obclient> SELECT ISNAN(1/0);
   

   The return result is as follows:

   +------------+
   | ISNAN(1/0) |
   +------------+
   |       NULL |
   +------------+
   1 row in set