Splunk Search

Foreach weird bug in variable

greggz
Communicator

So I have this chunk of code

eval matched=0 | foreach UF* [eval matched = if(like('<<FIELD>>',valMask),matched+1,matched) | eval Property = if(matched>=1,Property,null)]

Amusingly if the matched variable equals 1, the Property will get null value, when I explicity say that if it is bigger or equal than 1, the Property should remain with her original value.

Proof matched = 1

alt text

Thoughts on this ?

Thanks

0 Karma
1 Solution

greggz
Communicator

So apparently, matched inside the foreach is still 0. Something like Lazy Evaluation, but I don't really know. Anyway.. this works

foreach UF* [eval matched = if(like('<<FIELD>>',valMask),matched+1,matched)] | eval Property =  if(matched>=1,Property,null) 

View solution in original post

0 Karma

greggz
Communicator

So apparently, matched inside the foreach is still 0. Something like Lazy Evaluation, but I don't really know. Anyway.. this works

foreach UF* [eval matched = if(like('<<FIELD>>',valMask),matched+1,matched)] | eval Property =  if(matched>=1,Property,null) 
0 Karma

elliotproebstel
Champion

The structure generally looks ok, so I'm kind of reaching here. Any chance Property was null before the second half of the foreach ran? If you remove the second eval clause, is Property always populated?

0 Karma

greggz
Communicator

The only possibility I'm seeing is that matched is still 0 inside the foreach. Like a lazy interation

0 Karma

greggz
Communicator

I removed the eval clause, and all the Properties get populated..

0 Karma

mayurr98
Super Champion

Can you try

eval matched=0 | foreach UF* [eval matched = if(like('<<FIELD>>',valMask),matched+1,matched) ]| foreach UF* [eval Property=if(matched>=1,Property,null)]
0 Karma

greggz
Communicator

Same result.. What was your reasoning ?

0 Karma
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!

SOK it to Me: Top 3 Benefits of Using Splunk Operator on Kubernetes that’ll Make ...

    Thursday, July 9, 2026  |  11:00AM–12:00PM PDT Duration: 1 hour (includes Q&A) Managing can feel like a ...

Upgrade Prep for 10.4, Network Observability Deep Dives, and More from Splunk Lantern

Splunk Lantern is Splunk’s customer success center that provides practical guidance from Splunk experts on key ...

Splunk Developer Day announcements: AI agents, MCP tools, Forecasting, and Custom ...

Splunk Developer Day was packed with product and platform updates for developers building in the AI ...