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Anonymous
Not applicable

What is optimized and unoptimized qvd ?

What is optimized and unoptimized qvd ?

4 Replies
ashwinishinde
Partner - Contributor III
Partner - Contributor III

hello,

You can think of an unoptimized load as reading the table one record at a time.

Whereas, the optimized load is reading in chunks of records at a time.

If your QVDis relatively small you will hardly notice a difference.  When you are working with larger QVDs you will definitely see the impact. 

Anonymous
Not applicable
Author

Can you please explain me in very basic level.

ashwinishinde
Partner - Contributor III
Partner - Contributor III

As per my knowledge , a simply way to define is:

A load from qvd with out any transformation is optimized load

A load from qvd with data transformation will be un- optimized

eg:

optimized

load * from a.qvd



un-optimized :

load if(column1='a', column2-1, column2-3) as new column,

*

from a.qvd

MK9885
Master II
Master II

Optimized QVD is 'As IS' fields with no transformation

Un-optimized is with transformation as Ashwini explained above

Optimized QVD always loads fast compared to Un-optimized. Even if you transform your QVD, store it and then read the QVd back again, so that it runs faster (if space is not an issue on server)