Set Analysis - Performance Issue

Wed, 14 Sep 2011 02:52:22 GMT

I have a straight table where I have about 7 expressions. I converted the expressions from normal if statements to if's with set expressions. The values appear correct, the filtering works fine. The only issue is performance. It seems when run side by side the converted expressions (set expressions) take noticably longer to refresh than the plain if statement expressions. Is there something wrong with the logic I use or is this an inappropriate use of Set Analysis?

Samples are as follows:

Original Expression:

Sum(IF([Field1] = ‘Var1’, [SomeSales], [SomeOtherSales]))

"Converted" Expression:

If([Field1] = 'Var1',

Sum({$<Field1 = {Var1'}>} [SomeSales]),

Sum({$<Field1 = {'Var2'}>} [SomeOtherSales]))

Set Analysis - Performance Issue

kaushiknsolanki — Wed, 14 Sep 2011 06:13:00 GMT

Hi,

First thing i would like to tell you that, the use of setanalysis is not proper.

Sum({$<Field1 = {Var1'}>} [SomeSales]), this expression itself contains the if statement. Meaning it will give you sum of SomeSales only if Field1 = Var1. So it will be purly for Var1.

Now as far as performance is concerned the 'if' within sum() takes less time to calculate then sum() in if statement.

Thus your converted expression takes more time to calculate then your first expression.

Hope you understood.

Regards,

Kaushik Solanki

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Set Analysis - Performance Issue

Set Analysis - Performance Issue