look for the "InstanceSelection" property of Entity in your Report Model.

Thanks it worked for me, but I don't know how to mark your reply as Answer. can you tell me?

I think I figured out the 2nd one. The entity in my model had a property called "InstanceSelection" with the value of "MandatoryFilter." I cannot completely explain what this property...

Thanks for your response, sorry for the replying late as I was not in town.

On your 3rd point, I think this is what we call Named Query on Data Source...

Thanks for the response.

@GrassHopper

We will be designing or providing the desired dataset for the adhoc reports to the business as I suppose there is not much to code...

Thanks

but I can't use any sql server, hv to implement without it