I am new to QV and started learning. i have a one question, in real time first do we create a .QVD's files and then use these files in QVW application or directly create the scripts with required tables and coulmns in .QVW. what is the general practice.
For me, using QVDs is a must, I usually have lots of data to load, some historic data which change once per year or never, and it does not make sense to reload from the database again.
Technically speaking, you can work without QVDs and I could even think of super fast reload scenarios (near real time, although not the right use case) where the less time you use to load, the better, and depending on the size, network, disk IOPS... saving everytime to QVD (especially if you are not going to reuse them) would not even be recommended.
On the other hand, it is could also happen that it is faster to reload from a QVD than from a RESIDENT table or from the source, so you heavily rely on QVD files.
As a rule of thumb, just store any table you load to a QVD file, and load from them as often as possible.
Thanks for your explanation. now i understand QVD files and exploring how to create and load qvd files into QVW.
Here i got one more question. we create qvd script files using qvw application. in real time when we deploy the qvd files into server do we need to deploy the qvd files and qvw files as well used to create the qvd files or only qvd is enough.
If you did not change the data in your database, only the created QVD files are enough, you can immediately download them into QVW applications. If the changes / addition of data were, it will be necessary to recreate the files QVD, and then already load them into QVW file of application.