topic Re: Lookup - performance killer in QlikView

Lookup - performance killer

Christian_Lauritzen — Fri, 28 Mar 2014 12:27:28 GMT

Below is a query where I used Lookup (despite warnings) to find the first value from the field FName.

LOAD O_orgno,

O_name,

ApplyMap('Company_OrgnoChange',F_orgno) as F_orgno,

ApplyMap('Company_NameChange',F_orgno,Lookup('FName','FOrg',F_orgno,'tmpLookup')) as F_name

Resident Final1 where isnull (KeepNames) and F_orgno <> '#Missing#';

And yes, it is SLOW... very much so.

How could I rewrite the load statement so it is fast, I guess not using Lookup?

jonathandienst — Fri, 28 Mar 2014 12:44:00 GMT

You could try nested ApplyMaps rather than a Lookup, something like:

ApplyMap('Map1', [Field1], ApplyMap('Map2', [Field2], 'Default'))

(Just guessing, as you have not provided any details what you are trying achieve with the lookup)

HTH

Jonathan

Christian_Lauritzen — Tue, 01 Apr 2014 07:13:25 GMT

Good suggestion. It turned out to be very much faster. A blink compared to seconds. Thanks!