topic Best Practice for filtering reports by variable in QlikView

Best Practice for filtering reports by variable

cliff_clayman — Thu, 06 Oct 2016 15:48:00 GMT

I have a variable for Current Year and Previous Year. I am creating some reports that have a lot of expressions in them that are dependent upon one or both of these variables. I am trying to figure out what is the best way to filter a report by just Current Year. Should I used a calculated dimension? Should I put the variable in each expression? I want to be consistent and utilize the best practice. Can someone please explain what is the best practice here?

Re: Best Practice for filtering reports by variable

Peter_Cammaert — Thu, 06 Oct 2016 15:51:53 GMT

Can you post an example of your documents? It is rather difficult to post a best practice for something that is highly context-dependent. Thanks.

Re: Best Practice for filtering reports by variable

cliff_clayman — Thu, 06 Oct 2016 16:04:22 GMT

I don't think a specific example will make much of a difference. I'm just looking at it from an overall perspective.

Store	Sales	Revenue
1	$1,000,000.00	$500,000.00
2	$2,000,000.00	$1,000,000.00
3	$3,000,000.00	$1,500,000.00
4	$4,000,000.00	$2,000,000.00
5	$5,000,000.00	$2,500,000.00

Take something as simple as this. This data includes values from all years. I want to be able to limit it to only the Current Year. Is it best to use a calculated dimension, define the variable in each expression, or some other way?

Re: Best Practice for filtering reports by variable

Peter_Cammaert — Thu, 06 Oct 2016 16:07:24 GMT

IMHO the easiest way to limit a chart to diplay just data for the current year is to use set analysis. But then again, I have no clue what the circumstances are.

Re: Best Practice for filtering reports by variable

cliff_clayman — Thu, 06 Oct 2016 16:14:31 GMT

So, using Set Analysis, I would always need to define the value for that field. Something like this...

Sum({$<Year={2016}>}Sales)

Re: Best Practice for filtering reports by variable

Peter_Cammaert — Thu, 06 Oct 2016 16:20:02 GMT

Not really. If you have a variable that defines "Current Year" in a numerical format (i.e. not as an expression) then you better use something like:

=Sum({$<Year = {$(vCurrentYear)}>} Sales)

This technique will perform a $-sign substitution before evaluating the expression. It allows you to change the value of the Current Year without changing any expression.