topic Re: Trouble with variables in QlikView

Trouble with variables

Fri, 11 Apr 2014 09:41:58 GMT

Hi everybody,

I have a selection on date like 18/03/2014

THEN max(DateExerNum) = 18/03/2014

who can explain why

This

SET vPriorMaxDate = "=addmonths(max(DateExerNum), -12)";

returns 31/12/1899 WRONG VALUE

This

SET vPriorMaxDate = "=(max(DateExerNum)-365)";

returns 18/03/2013 RIGHT VALUE

Best regards

Chris

Re: Trouble with variables

tresB — Fri, 11 Apr 2014 09:54:48 GMT

Could you post a sample that demonstrates the issue?

Re: Trouble with variables

ThornOfCrowns — Fri, 11 Apr 2014 10:01:49 GMT

Hi, I did a little inline load and put your two SET expressions in the load script. Both return the same correct result when used in a text box, for example.

What are you doing to set DateExerNum?

Re: Trouble with variables

Fri, 11 Apr 2014 10:03:04 GMT

Its evaluating the first expression. But I dont understand the dfference between let and set here..both of them working in a similar way. I have used this exp:

set v2="=addmonths(max(Date),-12)";

This works fine.

Re: Trouble with variables

ThornOfCrowns — Fri, 11 Apr 2014 10:05:53 GMT

Let: Calculates the expression assigned to it and sets the expression result to the variable.

Set: Assigns the value(or expression which is after the equal sign) as it is without compute.

Example:

Set vVar=2+3; //vVar has the expression 2+3 as value and you have to compute it using $(vVar) which returns 5

Let vVar=2+3;//vVar has the computed value 5

It doesn't matter too much with strings, as in this case, as it works either way.

Re: Trouble with variables

Gysbert_Wassenaar — Fri, 11 Apr 2014 10:06:04 GMT

The addmonths function will return a date as a dual value, e.g. with a numeric value and as a formatted string. That string is probably not interpreted as a date when you use it later, but instead as 18 divided by 3 divided by 2013. That returns a very small number (close to 0) that when shown as a date returns a date close to the start of the calendar (day zero).

Re: Trouble with variables

Fri, 11 Apr 2014 11:19:18 GMT

Hi Gysbert,

Yes i could check the result hasn't a date format but i can't use date function like

SET vPriorMaxDate = "=date(addmonths(max(DateExerNum), -12))";

which returns the same wrong result

Thank you everybody for your answers

Chris

Re: Trouble with variables

Fri, 11 Apr 2014 11:39:59 GMT

Thank you Gysbert

you gave me the missign clue

SET vPriorMaxDate = "=num(addmonths(max(Bud.DateExerNum), -12))";

best regards

Chris