if i have three different sources ie oracle,sap,xml what will be the performance of the qv application

[#1]

if i have three different sources ie oracle,sap,xml what will be the performance of the qv application 

[its_anandrjs]

Try to use the QVDs of all the databases and not read direct data. First read the data from the raw source weather it is oracle,sap,xml and then create the QVDs and then load all this QVDs into the Qlikview In-memoey then it will give good performance.

And try always read the optimized QVDs.

[maxgro]

If I understand (I suppose the question is "performance of Qlikview when there are 1, 2, ....n different data sources"), I would split the question in 2, performance for users, performance for reload data:

- for the users, there is no difference as in the analysis phase (qlik and view) Qlikview uses his own in memory database and this in memory database, once built, is independent from source database (oracle, sap,....)

-  in the phase of reloading data (etl) the performance (time  of reload) depends on a diffferent number of things (number of tables, complexity of the source database, size of tables, etc, ......) but I would say is not (or a little) dependent on the number of different data sources; why? because in Qlik script you can easily mix (join) different data sources.

Anand suggested some good ways to reduce reload time. I would add incremental load.