Boolean Operations in Information Link Prompts


I've searched the web all morning and don't seem to be able to find anything on this topic... I'm sure this questions has been answered many times so if you know where, please let me know!

I would like to create and on-demand data table where the input from table Aggro kpi is typically values from column [Blank_Serial]. However, there is cases where there is no value in column [Blank_Serial]. In those cases (and only in those!) I would like to use column [Job] as an input instead. This is what I have so far using an information link for the on demand data which has no prompts:

    On-demand settings:
        Column BLANK_SERIAL filtered by:
            Expression: [Aggro kpi].[Blank_Serial]
        Column JOB filtered by:
            Expression: [Aggro kpi].[Job]
        Select to load automatically
        Select to allow caching

The problem with this is though that it seems to be a Boolean AND such that [Job] is used as an input filter in all cases and not just where [Blank_Serial] IS NULL.

Alternatively I thought the information link used for the on demand data could prompt for [Blank_Serial] OR [Job] but again I can't find instructions how to apply Boolean OR to prompts in information links.

Any idea, how I can limit the data the way I would like to would be highly appreciated.


(1) Answer