topic Re: Peek in TextBox in QlikView

Peek in TextBox

marco_puccetti — Thu, 12 Mar 2015 10:06:49 GMT

Hello, when i try to use this function: =peek('PRODOTTO', 1,'FATTI') in a TextBox or in a Variable, the sintax checker return error.

Is there anything i have done wrong?

PRODOTTO is the field, 1 is the record and FATTI is the table.

Thanks

Re: Peek in TextBox

prma7799 — Thu, 12 Mar 2015 10:11:22 GMT

I think we can not write peek function in text box.

Re: Peek in TextBox

tresB — Thu, 12 Mar 2015 10:11:30 GMT

Peek() is a script function.

Re: Peek in TextBox

mukesh24 — Thu, 12 Mar 2015 10:21:34 GMT

Peek() is inter record function & it is use in back end scripting

Re: Peek in TextBox

Gabriel — Thu, 12 Mar 2015 10:21:41 GMT

Hi,

As said above Peek function is a script function can't be used in UI. However, if you explain what you want to achieve may be someone might point you in right path.

If you are just debugging and wanting to know what the peek function (variable) would return. Then insert EXIT SCRIPT after the peek, reload and go to UI put the variable in a Text box. Dollar sign expand it

Re: Peek in TextBox

sunny_talwar — Thu, 12 Mar 2015 10:33:26 GMT

If you want the first record from the that field name, you can try something like this:

=SubField(Concat(DISTINCT PRODOTTO, '|'), '|', 1)

The only issue is that the Concat will do a ascending order concatenation and instead of getting the very first entry from that table, you will get first value in the ascending order. To fix this you will have to add a column in your script which would be something like this:

FATTI:

LOAD PRODOTTO,

RowNo() as ID

and so on...

FROM XYZ;

and then use this expression:

=SubField(Concat(DISTINCT PRODOTTO, '|', ID), '|', 1)

Now you concat function will be based on the ID field and your SubField will give you the very first entry from your PRODOTTO field.

HTH

Best,

Re: Peek in TextBox

Thu, 12 Mar 2015 11:02:59 GMT

Hi Marco,

Try this let function in scripting and then use variable in text box.

FATTI:

Load

Sum(PRODOTTO) as PRODOTTO

resident main_table;

Let variable=peek('PRODOTTO', 0,'FATTI')

Thanks ,

krish

Re: Peek in TextBox

nikhilgarg — Thu, 12 Mar 2015 11:11:43 GMT

Hey,

Peek function is not supported in Textbox then how have you used it in textbox. You may tell the description of task you want to do then only any of us may help you.

thanks

Re: Peek in TextBox

anbu1984 — Thu, 12 Mar 2015 11:42:12 GMT

Try FieldValue() like below in Text box

=FieldValue('PRODOTTO',1)

Re: Peek in TextBox

jonathandienst — Thu, 12 Mar 2015 11:48:25 GMT

anbu's suggestion is correct, providing PRODOTTO is not a key field (ie present in more than one table in the table viewer.

If PRODOTTO is a key field, you will need to do something in the load script to mark the record with a flag field, or Peek() it into a variable which you can then use in your expression. This also works if it is not a key field.

HTH

Jonathan

Re: Peek in TextBox

marco_puccetti — Thu, 12 Mar 2015 12:18:56 GMT

I have tried with this: Let m_Prod = peek('PRODOTTO', 0,'FATTI');

and debugging the script it returns the first data of the column PRODOTTO (that is prod A), but if i insert the $(m_Prod) in the text field it will return this error: "Error Garbage after expression: A".

Can you help me?

Thanks

Re: Peek in TextBox

sunny_talwar — Thu, 12 Mar 2015 12:21:18 GMT

What happens when you put =m_Prod (without the $ and parenthesis) in a text object?

Re: Peek in TextBox

marco_puccetti — Thu, 12 Mar 2015 12:23:49 GMT

It works, but is not always necessary the $ expansion before each variable reading?

Thanks

Re: Peek in TextBox

marcus_sommer — Thu, 12 Mar 2015 12:25:36 GMT

The suggestion from anbu cheliyan worked if you need to access distinct fieldvalues. If you need to access a fieldvalue from a certain table-record you need to extend these table with a rowno() ID which you then could use within the expression:

only({< RowNoID = {1}>} PRODOTTO)

- Marcus

Re: Peek in TextBox

sunny_talwar — Thu, 12 Mar 2015 12:27:01 GMT

Nope, $() is used when you have to evaluate a variable. If you just need the value from the variable without evaluating it, you don't use $().

In your case, when you used Peek function it spits out a value which can then be used without the $().

Best,

Re: Peek in TextBox

marco_puccetti — Thu, 12 Mar 2015 13:22:10 GMT

Can you make me some examples?

Thanks!!

Re: Peek in TextBox

sunny_talwar — Thu, 12 Mar 2015 13:31:51 GMT

Look at the attached qvw. You might find this helpful.

Note: there are two variables and both will give you different result for with and without $()

HTH

Best,

Re: Peek in TextBox

marco_puccetti — Mon, 16 Mar 2015 08:33:46 GMT

Thanks

Marco