topic Re: Condition (if - then) inside a load procedure in QlikView

Condition (if - then) inside a load procedure

Wed, 25 Nov 2020 16:16:04 GMT

Can I insert a condition (if - then) inside a load procedure?

ex:

CLIENTI:

load

cod_cliente as id_cliente,

cod_agente as id_agente,

if(vDocumentName='Example') then

cod_raccolta as id_raccolta,

end if

flag_intest as intest

from Cliente.qvd

I hope I was clear enough.

thx!!!

Re: Condition (if - then) inside a load procedure

avinashelite — Mon, 23 Jan 2017 11:42:53 GMT

Yes you can

if A>0 then

Code

End if

Re: Condition (if - then) inside a load procedure

avinashelite — Mon, 23 Jan 2017 11:43:19 GMT

If..then..elseif..else..end if

The if..then control statement is a script selection construct forcing the script execution to follow different paths depending on one or several logical conditions. The syntax is:

if condition then

[ statements ]

{ elseif condition then

[ statements ] }

[ else

[ statements ] ]

end if

Where:

condition is a logical expression which can be evaluated as true or false.

statements is any group of one or more QlikView script statements.

Since the if..then statement is a control statement and as such is ended with either a semicolon or end-of-line, each of its four possible clauses (if..then, elseif..then, else and end if) must not cross a line boundary.

Examples:

if a=1 then

load * from abc.csv;

sql select e, f, g from tab1;

end if

if a=1 then; drop table xyz; end if;

if x>0 then

load * from pos.csv;

elseif x<0 then

load * from neg.csv;

else

load * from zero.txt;

end if

Re: Condition (if - then) inside a load procedure

MK_QSL — Mon, 23 Jan 2017 11:44:39 GMT

What exactly you want to do in load script?

Can you describe little more please?

Re: Condition (if - then) inside a load procedure

Mon, 23 Jan 2017 11:57:14 GMT

But have you seen the example that I have attached together with my application?

I have to choose whether or not to load a FIELD according to the document name.

FIELD, NOT QVD

Re: Condition (if - then) inside a load procedure

sunny_talwar — Mon, 23 Jan 2017 12:14:45 GMT

What is vDocumentName here? a variable? How do you determine its value?

Re: Condition (if - then) inside a load procedure

marcus_sommer — Mon, 23 Jan 2017 12:15:54 GMT

You could implement an if-loop as a control-statement outside from a load-statement (take a look on the suggestion from avinashelite) or within the load as a function. In your case you could with:

CLIENTI:

load

cod_cliente as id_cliente,

cod_agente as id_agente,

if(DocumentName()='Example'), cod_raccolta, null()) as id_raccolta,

flag_intest as intest

from Cliente.qvd (qvd);

load these fieldvalues or NULL or any default-value within a new field but you couldn't avoid the creation of this new field. I think better than this would be the following:

CLIENTI:

load

cod_cliente as id_cliente,

cod_agente as id_agente,

cod_raccolta as id_raccolta,

flag_intest as intest

from Cliente.qvd (qvd);

if DocumentName() <> 'Example' then

drop fields id_raccolta;

end if

because your table will have this field only if the condition is met and your load will be remain optimized because no transforming is made unless the renaming which won't break it.

- Marcus