What's happening when you try to change?
Thanks for responding , I got resolved this issue. Initially i am able to change the data source for sheets where i have used tables but am unable to change for sheets where i used Custom SQL Query .It's throwing a error like '' WORKSHEET UNAVAILABLE'' custom sql query converting to RED color and fields with Exclamatory mark . even though i have same number of columns and same data type in both Data sources .
Custom SQL Query underlined with execution of actual data source , so we must need access to execute it & Utilize . Previously there was no access . That's the major problem