Splunk Search

Which is better NOT or !=

skeetermurphy
Engager

Here are two searches that are the same.

NOT FIELD="value"

FIELD!="value"

Which should be used? Is this just a personal preference or are there any performance differences between the two.

There are lots of cases where the NOT prefixes a much more complex search, but I'm just wondering about this simple case.

1 Solution

gkanapathy
Splunk Employee
Splunk Employee

These two searches are not the same.

NOT field="value" will return events where field is undefined (or null). field!="value" will only return events where field exists (and does not have the value "value").

In the case where the value in question is "*", NOT field=* will return events where field is null/undefined. field!=* will never return any events.

View solution in original post

gkanapathy
Splunk Employee
Splunk Employee

These searches are not the same. See below.

gkanapathy
Splunk Employee
Splunk Employee

These two searches are not the same.

NOT field="value" will return events where field is undefined (or null). field!="value" will only return events where field exists (and does not have the value "value").

In the case where the value in question is "*", NOT field=* will return events where field is null/undefined. field!=* will never return any events.

Get Updates on the Splunk Community!

SplunkTrust Application Period is Officially OPEN!

It's that time, folks! The application/nomination period for the 2025 SplunkTrust is officially open! If you ...

Splunk Answers Content Calendar, June Edition II

Get ready to dive into Splunk Dashboard panels this week! We'll be tackling common questions around ...

Splunk Observability Cloud's AI Assistant in Action Series: Auditing Compliance and ...

This is the third post in the Splunk Observability Cloud’s AI Assistant in Action series that digs into how to ...