Preceeding load problem

[ananyaghosh]

hi,

I am using the below code:

[Table]:

load*,

date(date#([Process Date Key],'YYYYMMDD'),'MM/DD/YYYY') as [Process Date];

Load

col1,

col2

.....

....

from a.qvd(qvd);

Now my table have 2billions records, and I noticed that when I use preceding load it load 4billions of data, though it does not duplicate the data. I observe this thing when I reload it and my data loading window just show me that it load data at just two times larger than actual data.

So my question is if I use preceding load, data loading will be slow down?

Thanks,

Sandip

[prma7799]

Please check this

Benefit of using Preceding load ..

http://help.qlik.com/en-US/qlikview/12.1/Subsystems/Client/Content/Scripting/preceding-load.htm

[Kushal_Chawda]

Generally we need to avoid preceding load on large data set due to performance issues. see below blog

http://qlikviewcookbook.com/2016/04/the-cost-of-preceding-load/