topic Re: eval isnull in Splunk Search

eval isnull

subtrakt — Mon, 28 Sep 2020 16:20:06 GMT

Hi!

Anyone know why i'm still getting NULL in my timechart?

The lookup "existing" has two columns "ticket|host_message". host_message column matches the eval expression host+CISCO_MESSAGE below... I **can get the host+message+ticket number to show up in the timechart with the following query - however if the results do not match host_message in the lookup, hostTICKET comes back null.** I want null to simply be host_message without the ticket because it does not exist on the lookup.

index=net | rex "(?i)^([^:]*:){8}(?<CISCO_LOG>.*)$" | eval host_message=host+CISCO_LOG | lookup existing host_message |  eval hostTICKET=if(isnull(hostTICKET),host_message+" "+TICKET,host_message) | timechart count by hostTICKET

Re: eval isnull

Ayn — Tue, 08 Apr 2014 08:08:32 GMT

You're using the wrong operator for performing string concatenations. It should be ".", not "+". So, your eval statement should read

eval hostTicket=if(isnull(hostTICKET),host_message." ".TICKET,host_message

Re: eval isnull

subtrakt — Tue, 08 Apr 2014 12:34:50 GMT

It is still coming back as NULL for messages that are not defined in the lookup. the field after "isnull" in parentheses is supposed to be the field that could come back as null correct?

Re: eval isnull

lukejadamec — Tue, 08 Apr 2014 13:22:23 GMT

No. NULL is being filled in by the lookup statement, so when it gets to the eval the values is NULL, which is not null.

Re: eval isnull

somesoni2 — Tue, 08 Apr 2014 13:29:53 GMT

Where is the field "hostTICKET" present? Its not coming from lookup right? Is it there in the logs?

Re: eval isnull

_brettfitz — Tue, 16 Feb 2021 19:48:48 GMT

The above eval statement does not correctly convert 0 to 0.0.0.0 and null values. Try this:

Note: replace ip with the field name you would like to convert.

| eval o1=floor(ip/16777216) | eval o2=floor((ip-o1*16777216)/65536) | eval o3=floor((ip-(o1*16777216+o2*65536))/256)| eval o4=ip-(o1*16777216+o2*65536+o3*256) | eval ipv4=tostring(o1)+"."+tostring(o2)+"."+tostring(o3)+"."+tostring(o4) | eval ipv4=if(ipv4="Null.Null.Null.Null","",ipv4)