not()

The not() function returns the logical negation (NOT) of a boolean value.

Syntax

Parameters

EXPR

The expression to evaluate as a boolean.

Description

The not() function evaluates EXPR. If the result is boolean true, it returns false. If the result is false, it returns true.

If EXPR is null or a non-boolean value such as a number or string, the function returns null.

The return type is always boolean or null.

Error codes

N/A

Usage examples

To prepare the WEB_APACHE_SAMPLE table used in these examples, refer to Preparing sample data.

1. Check whether the status code is not 200

   table limit=5 WEB_APACHE_SAMPLE | eval result = not(status == 200) | fields status, result
   

2. Filter requests that are neither GET nor POST

   table limit=5 WEB_APACHE_SAMPLE | search not(in(method, "GET", "POST"))
   | # Only request records that are not GET or POST are returned.
   

3. Filter User-Agents that are not crawlers

   table limit=5 WEB_APACHE_SAMPLE | eval is_bot = match(agent, "(?i)bot|crawler") | search not(is_bot)
   | # Only request records that are not crawlers are returned.
   

4. NULL input

   json "{'val': null}" | eval result = not(val)
   | # result: null
   

Compatibility

The not() function is available since before Sonar 4.0.