topic Re: Performance question in QlikView

Performance question

eleni_theodorid — Thu, 24 Sep 2015 07:49:47 GMT

Hi,

I have to create a whole app that is going to calculate something when a field selection is A and something else when the field selection is B.

Which is better solution from performance scope?

1. Create one expression to every single object that use this logic if(GetSelectedCount(FieldA])>0 , sum(FieldB), sum(FieldC))

2. Or else create two separate expressions with condition on expession?

Keep in mind that I have to do that on every single object in the app and there are really a lot of objects (which are using conditional show on object).

Pleased for your advise,

Helen

Re: Performance question

Thu, 24 Sep 2015 15:06:05 GMT

How about doing this condition in the script.

Re: Performance question

eleni_theodorid — Thu, 24 Sep 2015 15:18:16 GMT

It has to be working dynamically and be responsive to the selections...

Re: Performance question

rwunderlich — Thu, 24 Sep 2015 15:31:56 GMT

Conditional expression would perform best, but as you hinted, may be difficult to maintain with a lot of objects.

Using a variable to select the expression will give you both performance and maintainability. Define a variable "mycalc" as follows:

=if(GetSelectedCount(FieldA])>0 , 'sum(FieldB)', 'sum(FieldC)')

Note the equal sign and he quotes around the expressions.

Then code the chart expression as:

$(mycalc)

-Rob

http://masterssummit.com

http://qlikviewcookbook.com

Re: Performance question

petter — Thu, 24 Sep 2015 15:36:51 GMT

A dynamic expression directly via a table and a link to the selection field:

Re: Performance question

eleni_theodorid — Fri, 25 Sep 2015 10:35:43 GMT

Thank you all guys,

I will testyour suggestions out and I will let you know.

Re: Performance question

Peter_Cammaert — Fri, 25 Sep 2015 10:50:14 GMT

Note that Petter's solution has one additional advantage that others may not have: you can make your Expression list configurable using an external file (e.g. an Excel file)

BTW Thanks Petter, the INLINE delimiter trick is something new I learned from your script.