Splunk Search

Strange behavior of an eval

rbochen
New Member
 "call" OR "exception1" OR "exception2" OR "exception3"
    | eval calls = if(like(message, "%call%"), 1, 0)
    | eval errors1 = if(like(message, "%exception1%"), 1, 0)
    | eval errors2 = if(like(message, "%exception2%"), 1, 0)
    | eval errors3 = if(like(message, "%exception3%"), 1, 0)
    | eval errors = errors1 + errors2 + errors3
    | eval allErrorsPerMile = round((errors*1000) / calls, 3)
    | stats sum(allErrorsPerMile), sum(errors1), sum(errors2), sum(errors3), sum(errors), sum(calls)

Straight to the point: "calls" eval do not work in calculations

allErrorsPerMile = round((errors*1000) / calls, 3)

even though im sure it contains some value(it can be seen on the screenshot)
Im also sure the

| eval allErrorsPerMile = round((errors*1000) / calls, 3)

works becouse if i put a number instead of "calls" it calculates it

Whats wrong there? maybe I should approach the problem differently?

alt text

Tags (2)
0 Karma
1 Solution

elliotproebstel
Champion

The eval command running on a per-event basis. This part of your search string:

 | eval calls = if(like(message, "%call%"), 1, 0)

is setting the value of calls to either 1 or 0. So on some events, you are dividing by 0, which will produce an error.

So let's talk about these lines:

| eval errors = errors1 + errors2 + errors3
| eval allErrorsPerMile = round((errors*1000) / calls, 3)

Are you actually intending to calculate allErrorsPerMile on a per-event basis? Or is this meant to be a value you are calculating across the sum of the errors in all events? If it's the latter, you'll need to do something like this instead:

| stats sum(errors1) AS errors1 sum(errors2) AS errors2 sum(errors3) AS errors3 sum(calls) AS calls 
| eval errors=errors1 + errors2 + errors3
| eval allErrorsPerMile=if(calls>0, round((errors*1000)/calls, 3), "Error: Trying to divide by zero")

By reversing the order of the stats and eval commands, you'll get totals across all events, rather than across individual events.

View solution in original post

0 Karma

elliotproebstel
Champion

The eval command running on a per-event basis. This part of your search string:

 | eval calls = if(like(message, "%call%"), 1, 0)

is setting the value of calls to either 1 or 0. So on some events, you are dividing by 0, which will produce an error.

So let's talk about these lines:

| eval errors = errors1 + errors2 + errors3
| eval allErrorsPerMile = round((errors*1000) / calls, 3)

Are you actually intending to calculate allErrorsPerMile on a per-event basis? Or is this meant to be a value you are calculating across the sum of the errors in all events? If it's the latter, you'll need to do something like this instead:

| stats sum(errors1) AS errors1 sum(errors2) AS errors2 sum(errors3) AS errors3 sum(calls) AS calls 
| eval errors=errors1 + errors2 + errors3
| eval allErrorsPerMile=if(calls>0, round((errors*1000)/calls, 3), "Error: Trying to divide by zero")

By reversing the order of the stats and eval commands, you'll get totals across all events, rather than across individual events.

0 Karma

mayurr98
Super Champion

The issue seems to be in output of eval errors
Can you tell me the output of errors? Is it coming propeR?

0 Karma
Get Updates on the Splunk Community!

Detecting Remote Code Executions With the Splunk Threat Research Team

REGISTER NOWRemote code execution (RCE) vulnerabilities pose a significant risk to organizations. If ...

Observability | Use Synthetic Monitoring for Website Metadata Verification

If you are on Splunk Observability Cloud, you may already have Synthetic Monitoringin your observability ...

More Ways To Control Your Costs With Archived Metrics | Register for Tech Talk

Tuesday, May 14, 2024  |  11AM PT / 2PM ET Register to Attend Join us for this Tech Talk and learn how to ...