topic Re: Where it save my QVD files? in QlikView

Where it save my QVD files?

danosoft — Mon, 26 Jan 2026 18:19:17 GMT

Hi i did this in my script for create a QVD file:

Buffer

SQL SELECT "DT_DATA",

"N_COLUMN1",

"PUN_COLUMN2"

FROM "XXX_TABLE"."V_PROXYTAB";

With "Buffer" i think QlikView create a Qvd file, but where? i not have the directory C:\ProgramData\QlikTech\QlikView\Buffers

Re: Where it save my QVD files?

vishsaggi — Fri, 22 Sep 2017 16:08:53 GMT

In your qvw file where you are using this Buffer Load. Just click Ctrl+ALt+U to open the User preferences and go to Locations tab there you can see default path. Like below:

Read here:

Buffer ‒ QlikView

Re: Where it save my QVD files?

danosoft — Fri, 22 Sep 2017 16:25:40 GMT

Thanks, is right, but it do to me the a strange name to the file, can i say to buffer to make a "human" name to the file? thanks

Re: Where it save my QVD files?

vishsaggi — Fri, 22 Sep 2017 16:50:15 GMT

What do you mean can you give an example. ? You want the QVD file name to be changed? May be you can modify the path from Modify button in Locations tab of User preferences.

Re: Where it save my QVD files?

Peter_Cammaert — Sat, 23 Sep 2017 14:42:05 GMT

Buffer files are not meant to be used by you or your script code as data sources. They are a behind-the-scenes technique to cache data that doesn't need to be extracted from the data source over and over again. QlikView manages those buffers, nobody else.

Re: Where it save my QVD files?

danosoft — Mon, 25 Sep 2017 06:36:23 GMT

Ah i understand..... this i want to do:

I have a big query it make response after 5 hours from Oracle, but i know the 80% of results (years before 2016) never change... so i want use the QVD files, i think it can resolve my situation... i want the query with years before 2016 never be changed, after this year from 2017 i want all day qlikview refresh my data; so i thought to use BUFFER expression... this is a wrong technics?

Thanks

Re: Where it save my QVD files?

Peter_Cammaert — Mon, 25 Sep 2017 07:11:57 GMT

Automatic buffering using the BUFFER prefix has numerous limitations. IMHO you better use a classical incremental LOAD technique (of which many examples are present in this community) along the lines of this pseudo-code:

IF IsNull(Filetime('HistoricalQVD.QVD')) THEN

LET vWhere =;

ELSE

LET vCutoff = '1/1/' & (Year(Today()) - 1);

BigTable:

LOAD * FROM HistoricalQVW.QVD (qvd)

WHERE DateField < '$(vCutoff)';

LET vWhere = 'WHERE DateField >= ' & chr(39) & '$(vCutoff)' & chr(39);

END IF

BigTable:

SQL SELECT * FROM BigOracleTable

$(vWhere);

Change this template to match your situation.

Best,

Peter

Re: Where it save my QVD files?

marcus_sommer — Mon, 25 Sep 2017 07:16:18 GMT

The general idea of using incremental loads with qvd's in a multi-tier data-architecture is the right one if you are not playing with a few rather small and simple applications. As soon as you have a bigger environment it made sense to handle all data explicitly and professional with store-statements to your preferred folder-structure - BUFFER is only for temporary single loads.

- Marcus

Re: Where it save my QVD files?

danosoft — Mon, 25 Sep 2017 07:18:05 GMT

Thanks, but i didn't want to create an incremental, i want give 2 query:

1. BUFFERED with old data (before 2016)

2. NOT buffered with new data (> 2017)

how can i do that?

i mean if i put BUFFER on top of my first query, qlikview automatically will be use the QVD file withouth take records from query?

Re: Where it save my QVD files?

Peter_Cammaert — Mon, 25 Sep 2017 07:21:20 GMT

Won't work. BUFFER limitations.

That's why you need an incremental LOAD, which does pretty much the exact same thing as the BUFFER prefix but better and more flexible.

Re: Where it save my QVD files?

danosoft — Mon, 25 Sep 2017 07:24:28 GMT

ok, and how can i generate the QVD file to use?

Re: Where it save my QVD files?

Peter_Cammaert — Mon, 25 Sep 2017 07:30:55 GMT

Just add the following pseudo-code to the end of the above template, after the SELECT statement. Every assembly of BigTable from either all Oracle data (because the historical QVD doesn't exist yet) or from part QVD/part Oracle will be written to the Historical QVD.

STORE BigTable INTO HistoricalQVD.QVD (QVD);

Re: Where it save my QVD files?

marcus_sommer — Mon, 25 Sep 2017 07:32:36 GMT

It's quite simple:

table:

load * from x;

store table into path\table.qvd (qvd);

Here you will find a lot stuff how to implement incremental loadings with where exists-clauses:

Advanced topics for creating a qlik datamodel

- Marcus

Re: Where it save my QVD files?

danosoft — Mon, 25 Sep 2017 07:58:26 GMT

I not understand well.... this is my case with this 2 query, how can i create QVD the first time and how can i load from QVD the second time and after?

This is my script:

CDG_EE:

LOAD ANNO,

"SOMMA_CONTI";

SQL SELECT *

FROM "TABLE_YEAR_16";

LOAD ANNO,

"SOMMA_CONTI";

SQL SELECT *

FROM "TABLE_YEAR_17";

I want put in the QVD file only the first query

Thanks

Re: Where it save my QVD files?

marcus_sommer — Mon, 25 Sep 2017 08:52:46 GMT

You could reach it just by loading the 2016 data first, storing the qvd and then commenting it out and loading afterwards the new data and the qvd-data or it could be also done within an if-loop:

CDG_EE:

LOAD ANNO, "SOMMA_CONTI";

SQL SELECT * FROM "TABLE_YEAR_16";

store CDG_EE into TABLE_YEAR_16.qvd (qvd);

CDG_EE:

LOAD ANNO, "SOMMA_CONTI";

SQL SELECT * FROM "TABLE_YEAR_17";

concatenate(CDG_EE)

load * TABLE_YEAR_16.qvd (qvd);

- Marcus

Re: Where it save my QVD files?

danosoft — Mon, 25 Sep 2017 08:55:20 GMT

That can be great if i can do an "If" if existing file qvd to load it or load the Sql

Thanks

Re: Where it save my QVD files?

marcus_sommer — Mon, 25 Sep 2017 09:06:13 GMT

Yes, in general you could do:

if condition then

load 1

else

load 2

end if

and in your case mybe:

if filetime('path\qvd-file.qvd') > 0 then

...

- Marcus

Re: Where it save my QVD files?

danosoft — Wed, 27 Sep 2017 12:20:12 GMT

Hi sorry but CONCATENATE(CDG_EE); command make me an error, it say: not found command concatenate

Re: Where it save my QVD files?

marcus_sommer — Wed, 27 Sep 2017 12:40:20 GMT

Did the message really say: "not found command concatenate" or was it rather "not found table CDG_EE"? The first message is unknown for me but the second one (from me mentioned) is quite common and happens if this table didn't exists which for example happens if already a table with this data-structure exists - no new table is created else the new load will be appended. If this didn't help please post your relevant script and a screenshot from the error-message.

- Marcus

Re: Where it save my QVD files?

danosoft — Wed, 27 Sep 2017 15:09:30 GMT

I find the solution, the error is concatenate(cdg_ee) it want CONCATENATE before my load table:

concatenate

CDG_EE:

LOAD ...,