topic Re: Boolean variables and conditional expressions in QlikView

Boolean variables and conditional expressions

Mon, 10 Feb 2014 09:30:03 GMT

Hello fellows,

I would like to write the following expression (pseudo-code):

// define boolean variable

let variable = true;

// check if boolean variable is true

if (true) then

// some code goes here

then

// other code

end if

QV's behavior seems to be totally cont-intuitive here, i.e. it doesn't properly check if (true) condition. SO far I've tried

- if ($(variable))

- if ($(variable) = True)

- if ($(variable) = true() )

- ...

Can someone explain how to work with boolean variables and conditional expressions?

Re: Boolean variables and conditional expressions

jonathandienst — Mon, 10 Feb 2014 09:31:46 GMT

True() is a function returning true (-1):

let variable = true();

and then

If($(variable), <true expr>, <false expr>)

HTH

Jonathan

Re: Boolean variables and conditional expressions

tresB — Mon, 10 Feb 2014 09:34:57 GMT

If <Condition> Then ....

for your case, you can try like:

Let variable=1;

If $(variable)=1 Then ...

Set variable='true';

If $(variable)='true' Then ...

Re: Boolean variables and conditional expressions

jonathandienst — Mon, 10 Feb 2014 09:37:40 GMT

And also:

let variable = true();

If variable Then

... script code ...

Else

... script code

End If

Re: Boolean variables and conditional expressions

maxgro — Mon, 10 Feb 2014 09:38:18 GMT

very good doc with explanation of boolean

http://community.qlik.com/blogs/qlikviewdesignblog/2012/12/07/booleans

Re: Boolean variables and conditional expressions

Mon, 10 Feb 2014 09:48:14 GMT

That's indeed a good article!

The problem behind was QV's way to treat variables in 'dual' form. Correct way to check a boolean value within a if expression would be either

if (variable = 'True') (note capital letter!)

if (variable <> 0)

Re: Boolean variables and conditional expressions

Anonymous — Mon, 06 Aug 2018 21:12:33 GMT

Let vMyVariable = True();

If '$(vMyVariable)' = 'True' Then

// business logic here

End If

// likewise, use False() and 'False'