topic Re: How to have the lookup multivalue field return the 1st match? in Splunk Search

How to have the lookup multivalue field return the 1st match?

brdr — Tue, 01 May 2018 18:33:53 GMT

hello,

I have a lookup table that has host to user correlation... ex;

Host, User
hosta, user1
hostb, user2
hostb, user3

My understanding is that when I match on hostb via lookup below I will get field Authentication.user back as a multivalue field. But when I try to use 'mv' commands to get first user for hostb (user2) I get blank field for top_user. Why? thx.

| makeresults | eval host="hostb"
    | table host
    | lookup host-to-users.csv Authentication.src as host OUTPUT Authentication.user
    | eval top_user=mvindex(Authentication.user,0)
    | table host Authentication.user top_user

Re: How to have the lookup multivalue field return the 1st match?

somesoni2 — Tue, 01 May 2018 18:46:35 GMT

If your lookup fields are host and user (that exact name), you're using wrong order in your lookup invocation. Do you get any value in Authentication.user right now?

Re: How to have the lookup multivalue field return the 1st match?

brdr — Tue, 01 May 2018 18:54:24 GMT

Hey somesoni2, yes I get the appropriate number of user(s) that match on host. Just not sure why I can't operate on the users mv field to get the first (value) user.

Re: How to have the lookup multivalue field return the 1st match?

woodcock — Tue, 01 May 2018 19:36:36 GMT

You have a mismatch in field names and wrong ordering to boot, with a dash of possible misinterpretation of . as concatenation operator. Try this:

| makeresults | eval host="hostb"
| table host
| lookup host-to-users.csv host AS Authentication.src OUTPUT user AS Authentication.user
| eval top_user=mvindex('Authentication.user', 0)
| table host Authentication.user top_user

Re: How to have the lookup multivalue field return the 1st match?

brdr — Tue, 01 May 2018 20:06:03 GMT

thx for response as always... I did have it backwards. the headers in the lookup file should have been Authentication.src, Authentication.user..

The thing that was catching me up is the single quotes around the first parameter in the mvindex() function. As soon as I added the quotes the commands I entered worked.

Thx again.

Re: How to have the lookup multivalue field return the 1st match?

woodcock — Tue, 01 May 2018 20:10:10 GMT

I hate non-alphanumeric characters in field names, especially spaces and periods.