topic Re: Do While Loop in QlikView

Do While Loop

Anonymous — Tue, 28 May 2013 09:17:27 GMT

I'm not sure if this is a problem with the syntax of my Do...While loop, or with the way I'm using variables in my script, but I've hit a brick wall and need some help.

I am currently writing a trigger mechanism for my Qlikview schedule and need my script to continue running until the trigger file has been altered.

So, I have one variable (vCurrentTriggerDate) taking the timestamp from the actual trigger file, and a second variable taking the timestamp stored in a QVD file (vStoredTriggerDate).

My loop reads like this:

Do while '$(vCurrentTriggerDate)'='$(vStoredTriggerDate)';

let vCurrentTriggerDate = Filetime('$(vCRSPath)$(vMCPath)TriggerTest.txt');

LOOP;

The idea being, that when the timestamp on 'TriggerTest.txt' changes, the script should drop out of the loop. However, I don't think it is ever re-evaluating the contents of vCurrentTriggerDate, and therefore continues looping forever.

Has anyone got any ideas how to overcome this?

Many thanks

Re: Do While Loop

flipside — Tue, 28 May 2013 09:50:39 GMT

Hi Andrew,

Try this ...

let vStoredTriggerDate=filetime({file});

let run = 1;

let pass = 1;

Do while run = 1

if vStoredTriggerDate<>Filetime({file}) then

let run = 0;

endif;

//testing

trace $(pass): Running;

sleep 100;

let pass = pass + 1;

LOOP;

flipside

Re: Do While Loop

Anonymous — Tue, 28 May 2013 10:20:28 GMT

Thanks so much for this. Worked a treat (with a little tinkering).