Splunk Search

How to create a regular expression on a multivalue field

jlkokko
Path Finder

I have a multivalue (MV) field "filetypes" with values such as:

test/Makefile.am,test/och_test.cc,test/fully1.py,24,FKP/pro.pl

I need to keep only the extension listed (such as am, cc, py, pl, etc..) so I have two questions:

A. The appropriate regular expression
B. Is it more appropriate to run a regex prior splitting a MV field or after?

1 Solution

somesoni2
Revered Legend

Try like this. It'll create a new field with just the extn.

your base search with file filetype
| rex field=filetypes max_match=0 "(?<extns>\.\w+)"

View solution in original post

jlkokko
Path Finder

Both of the above worked well...wondering if one less expensive than the other

0 Karma

woodcock
Esteemed Legend

Like this:

... | mvexpand filetypes | rex field=filetypes "^(?<file_prefix>.+)\.(?<file_suffix>[^\.]+)$"

woodcock
Esteemed Legend

Mine was geared towards enabling the later commands that you will surely be interested in doing. You can look at the Job Inspector to compare efficiencies.

0 Karma

somesoni2
Revered Legend

Try like this. It'll create a new field with just the extn.

your base search with file filetype
| rex field=filetypes max_match=0 "(?<extns>\.\w+)"
Got questions? Get answers!

Join the Splunk Community Slack to learn, troubleshoot, and make connections with fellow Splunk practitioners in real time!

Meet up IRL or virtually!

Join Splunk User Groups to connect and learn in-person by region or remotely by topic or industry.

Get Updates on the Splunk Community!

Why Splunk Customers Should Attend Cisco Live 2026 Las Vegas

Why Splunk Customers Should Attend Cisco Live 2026 Las Vegas     Cisco Live 2026 is almost here, and this ...

What Is the Name of the USB Key Inserted by Bob Smith? (BOTS Hint, Not the Answer)

Hello Splunkers,   So you searched, “what is the name of the usb key inserted by bob smith?”  Not gonna lie… ...

Automating Threat Operations and Threat Hunting with Recorded Future

    Automating Threat Operations and Threat Hunting with Recorded Future June 29, 2026 | Register   Is your ...