topic Re: Incremental reload and store into QVD file in QlikView

Incremental reload and store into QVD file

Anonymous — Tue, 06 Mar 2012 08:53:30 GMT

Hi all,

To find out how incremental reload and storing into a QVD file works, I made an example document (find it attached).

It works fine, but the exact way it works is unclear to me. Maybe one of you can help me out.

Lets assume that there is a lot data in the database I would like to load. Because of that, I would like to load the data once. After that, only new rows will be inserted into the QVD file. But, ss this the way my example works? It seems to me, that all the data will be load during a reload of the document, and not only new rows will be inserted but a whole new load will be stored into the QVD. Is that right? If so, how can I make it work so that only new rows will be inserted?

I hope someone can explain the me.

Kind regards,

Henco

Re: Incremental reload and store into QVD file

jagan — Tue, 06 Mar 2012 09:07:12 GMT

Hi,

Use this script

LET lastReloadTime = ReloadTime();

GA_DATA:

LOAD

PK,

Calendardate,

Revenue

FROM (qvd);

CONCATENATE

LOAD

PK,

Calendardate,

Revenue

FROM

(ooxml, embedded labels, table is Sheet1)

WHERE (Calendardate > $(lastReloadTime));

store GA_DATA into ;

Hope this helps you.

Regards,

Jagan.

Re: Incremental reload and store into QVD file

Tue, 06 Mar 2012 09:12:33 GMT

Hi Henco,

please see also QV Help: Using QVD Files for Incremental Load

Good Luck!

Rainer

Incremental reload and store into QVD file

jagan — Tue, 06 Mar 2012 09:13:01 GMT

Hi,

Check this URL

http://community.qlik.com/message/68515#68515

Regards,

Jagan.

Incremental reload and store into QVD file

Anonymous — Tue, 06 Mar 2012 09:16:42 GMT

Thanks for your quick reply. I think I understand what you mean and that will be helpful.

There is one thing I am worried about. At first the document loads the data from the database, to store it into the QVD file:

DATA:

LOAD PK,

Calendardate,

Revenue

FROM

(ooxml, embedded labels, table is Sheet1);

store DATA into ;

What happens when I reload the document? Is it going to do a full reload and store all the data into the qvd file? Because that is exactly something I want to avoid.

I read the other question you linked to, but to sure I ask this question.

Kind regards,

Henco

Incremental reload and store into QVD file

jagan — Tue, 06 Mar 2012 10:11:30 GMT

Hi,

You need to check whether QVD exists, if QVD exists then load from QVD, otherwise load data from Datasource.

You need to restrict Full reload by this way.

LET lastReloadTime = ReloadTime();

If qvdcreatetime("QVDFilePath") Then

GA_DATA:

LOAD

PK,

Calendardate,

Revenue

FROM (qvd);

ELSE

GA_DATA:

LOAD PK,

Calendardate,

Revenue

FROM

(ooxml, embedded labels, table is Sheet1);

END IF

CONCATENATE (GA_DATA)

LOAD

PK,

Calendardate,

Revenue

FROM

(ooxml, embedded labels, table is Sheet1)

WHERE (Calendardate > $(lastReloadTime));

store GA_DATA into ;

Hope this helps you.

Regards,

Jagan.

Incremental reload and store into QVD file

Anonymous — Tue, 06 Mar 2012 10:13:38 GMT

Thanks again Jagan! This will really help me out.

Regards,

Henco

Re: Incremental reload and store into QVD file

Tue, 07 May 2013 10:40:53 GMT

Hi Jagan,

I tried both scripts as mentioned above, but got the same error:

Error in expression:

')' expected

CONCATENATE (GA_DATA)

LOAD

PK,

Calendardate,

Revenue

FROM

(ooxml, embedded labels, table is Sheet1)

WHERE (Calendardate > 7-5-2013 18:37:59)

May I know how to solve this?

Re: Incremental reload and store into QVD file

Mon, 03 Jun 2013 14:47:47 GMT

Hi, I´ve been gettin the same error, I apparently solved it by replacing the let sentence for a set sentence,

when establishing the lastReloadTime variable.

Try it and let me know, because I´ve been getting some errors but I´ve been able to solve them one by one

Regards

Re: Incremental reload and store into QVD file

Anonymous — Tue, 15 Apr 2014 03:59:19 GMT

add code in the where clause

CalenderDate>date('$(lastReloadTime)','MM-DD-YYYY')

It will work.

Re: Incremental reload and store into QVD file

Thu, 21 Aug 2014 12:39:27 GMT

Hi Friends

Your Suggestions Were Informative ,But What if the new data that is loaded has a possibility of changing for period say 1 week from its date of entry into the Data Base.

At these Situation "ReloadTime()" may not the perfect Option....!

Can Any one suggest me a solution for this problem....?

Thanks In Advance

Re: Incremental reload and store into QVD file

Karthik3 — Tue, 24 Feb 2015 12:00:22 GMT

If you have a changed date field in your tables then you need to use it.