topic Why isn't my where clause working in this similar search? in Splunk Search

Why isn't my where clause working in this similar search?

pranaynanda — Tue, 26 Sep 2017 12:33:43 GMT

I want to run a search but can't figure out what's the difference when I make changes to it using the 'where' clause

What's the difference between

...base search extension!=NULL|where Module="previewservice" | chart count by  Module, FinalState

and

  ...base search |where Module="previewservice" AND extension!=NULL| chart count by  Module, FinalState

The first one produces an output while the second one does not 😕

Re: Why isn't my where clause working in this similar search?

RPiccone — Tue, 26 Sep 2017 12:48:02 GMT

Your first search string is the more efficient of the two, as it's best to exclude as early as possible. However, to make the second example work, replace
And extension!=NULL
with
isnotnull(extension)

This is because where uses eval expressions, one of which is the function isnotnull. In your second example extension!=NULL is actually interpreted as <fieldA> is not equal to <fieldB> (where <fieldB> is a non-existent field called NULL).
For reference, see the documentation on Informational Functions (http://docs.splunk.com/Documentation/SplunkCloud/6.6.1/SearchReference/InformationalFunctions)

Re: Why isn't my where clause working in this similar search?

pranaynanda — Tue, 26 Sep 2017 13:06:31 GMT

Salut! You Sir are a true genius!