topic Re: Create new fields using values from another field in Splunk Search

Create new fields using values from another field

bt149 — Mon, 21 Jul 2025 14:59:56 GMT

I have a field called key. key has multivalues that are also dynamic. I have another field called values, that is also multivalued and dynamic. The values in "values" line-up with the values in "key".

Example:

key	values
AdditionalInfo	user has removed device with id alpha_numeric_field" in area "alpha_numeric_field" for user "alpha_numeric_field".
DeviceID	alpha_numeric_field
DeviceType	mobile_device
OS	Windows

Thanks in advance and I hope this makes sense.

I want to create a new field using the values from the field "key" and have the values be the values from "values".
The oucome would be:

AdditionalInfo	user has removed device with id alpha_numeric_field" in area "alpha_numeric_field" for user "alpha_numeric_field".
DeviceID	alpha_numeric_field
DeviceType	mobile_device
OS	Windows

Re: Create new fields using values from another field

kiran_panchavat — Mon, 21 Jul 2025 15:18:28 GMT

@bt149

Re: Create new fields using values from another field

bt149 — Mon, 21 Jul 2025 15:30:09 GMT

I appreciate the help, but this is not what I'm looking to do. I want to create the new fields so they could be used for searching. I already have a field using the mvzip command. Thanks again.

Re: Create new fields using values from another field

PickleRick — Mon, 21 Jul 2025 20:02:51 GMT

For creating fields dynamicaly you can use the {} syntax. Like

| makeresults
| eval field="field1",{field}="value"

But the important question and a possible issue here is where did you get the multivalued fields from. Remember that two distinct multivalued fields are... well, distinct. There is no relationship between their values whatsoever. And if you are creating multivalued field by means of list() or values() and the original data didn't have some values, you can't tel, which ones were empty. You're just getting a "squashed" list as a result.

Re: Create new fields using values from another field

yuanliu — Tue, 22 Jul 2025 05:43:28 GMT

First, I suspect that you meant the input looks like

key	values
AdditionalInfo DeviceID DeviceType OS	user has removed device with id "alpha_numeric_field" in area "alpha_numeric_field" for user "alpha_numeric_field". alpha_numeric_field mobile_device Windows

Second, I have a question about the origin of "key" and "values". Could they come from a structure such as JSON? Maybe there is a better opportunity than at the end of processing.

Third, I suspect that you meant "the output would be"

AdditionalInfo	DeviceID	DeviceType	OS
user has removed device with id "alpha_numeric_field" in area "alpha_numeric_field" for user "alpha_numeric_field".	alpha_numeric_field	mobile_device	Windows

Finally, if your Splunk is 8.1 or later, you can use JSON functions and the multivalue mode of foreach to do the job:

| eval idx = mvrange(0, mvcount(key)) | eval keyvalue = json_object() | foreach idx mode=multivalue [eval keyvalue = json_set(keyvalue, mvindex(key, <<ITEM>>), mvindex(values, <<ITEM>>))] | spath input=keyvalue | fields - idx key values keyvalue

Here is an emulation for you to play with and compare with real data

| makeresults format=csv data="key,values AdditionalInfo,user has removed device with id \"alpha_numeric_field\" in area \"alpha_numeric_field\" for user \"alpha_numeric_field\". DeviceID,alpha_numeric_field DeviceType,mobile_device OS,Windows" | stats list(*) as * ``` data emulation above ```

Re: Create new fields using values from another field

bt149 — Tue, 22 Jul 2025 11:14:49 GMT

This looks very promising. Thank you for your valued input!