topic Ignoring fields by IF in QlikView

Ignoring fields by IF

Fri, 10 Jul 2009 14:08:40 GMT

Hi all,

over the time my QlikView application became a bit slow. I mainly use simple expressions like "Sum(Revenue)". (In performance tests I already sorted out the more complex expressions)

The sluggish performance is only disturbing, if in ONE certain field (valuetype) no selection is made.
So I thought about a simple solution to calculate the Sum only if a selection is made.

=if(GetSelectedCount(valuetype)=0,0,Sum(Revenue))

This works in terms of returning 0 in case no selection is made, but the (bad) performance is as it was before.
The idea is to calculate the Sums only if a selection is made for valuetype, otherwise just return 0 ("do not even touch the Sum formula"). I thought this should be faster than any Sum(if(a=b,myfield)) or Sum({a=b}myfield) approach, where the Sum-function must at least do 'something'.
But it is not ....

Any thoughts on this?
Thank you,

Thilo

Ignoring fields by IF

Fri, 10 Jul 2009 17:25:40 GMT

If it is okay to display the chart only when some selections are made, then you could try this:

In the chart properties, you can put calculation condition "getselectedcount(valuetype) > 0". This will show the chart only when some selection is made else will display a message which can be customized (Properties/General/Error Messages).

Thanks

Amit

Ignoring fields by IF

Mon, 13 Jul 2009 02:43:49 GMT

Hello Amit,

yes - I can imagine this as a workaround.

But still I'd like to understand QlikView in more detail.

In case of a formula like "if (condition, expression1, expression2)" ... when is 'expression2' processed?
I would expect that this is done only in case of 'condition = false'.
Does QlikView work this way?

Thank you,
Thilo