Is bad practice to concatenate several resident loads from a big optimized qvd load?

[julioarriaga]

Hi everyone,

As always, I appreciate all the support and help from the community.

I want to optimize an app that I didn't develop that has the following structure divided in two sheets:

Sheet1:
BigTable:
LOAD *
FROM QVD.qvd (qvd);

//Certain business section
Sheet2:
FinalTable:
LOAD Field1
          ,FieldN
RESIDENT BigTable
Where FieldN='Value' OR FIELDM='Other Value';

//Another business section
Concatenate
LOAD Field1
          ,FieldN
RESIDENT BigTable
Other set of where clauses;

drop table BigTable;

I have two ideas of optimizing this stuff. Which one is more efficient? I'm open to other suggestions.

1) Load the concatenated parts just directly from the big QVD.

2) Or do a big load ordered by the lots of different where clauses for each business section..

Thanks a lot, in advance.

[felipedl · Accepted solution]

The QVD file will load faster if you do minimal where statements to it, see this article:

optimize and non-optimze load in qvd

What you could do, is section your big QVD file into Year Month for example or some other type of aggregation to make the calculations faster for each splitted part.

Felipe.