How to use "OR" in the SET Analysis

[#1]

I have created an expression (which works perfectly):

= SUM ({<[User Comments 4WKS] = {"$(vUC4WKSCombined)"}> [User Comments 4WKS])

variable (vUC4WKSCombined) contains values from 0 to 100

but there are also NULL values for dimension [User Comments 4WKS]

Now my question is how can I change my expression so it can take care of both varialbe values from 0 to 100 and also NULL values

I need OR condition between two set modifiers, like dimesion  [User Comments 4WKS] can either take any values from 0 to 100 OR is NULL

= SUM ({<[User Comments 4WKS] = {"$(vUC4WKSCombined)"} or [User Comments 4WKS] = {"NULL"}> [User Comments 4WKS])

Can someone look into this and write the correct experssion?

Thanks,

TA

[#2]

Hi Gysbert,

Thanks for your help once again. Just a quick question though:

I will highly appreciate if you explain the logic of this expression as well.

= SUM ({<[AU ID] = {"=sum([User Comments 4WKS])$(vUC4WKSCombined)"}>  *

<[AU ID] = {"=sum([User Comments 26WKS])$(vUC26WKSCombined)"}> *

<[AU ID] = {"=sum([User Comments 52WKS])$(vUC52WKSCombined)"}>}[User Comments 4WKS])