In this tutorial i will show how to solve the error "Unable to update the EntitySet because it has a DefiningQuery and no element exists in the element to support the current operation". What exactly i got is,
Unable to update the EntitySet 'table' because it has DefiningQuery and no DeleteFunction element exists in the ModificationFunctionMapping element to support the current Opereation" This error i was getting while updating the record to the table. Finally i understood it is due to the primary key was removed. After enable the primary key and update the entity .edmx file it works properly. Then also if it is not worked next delete the entity model and create model. Build the project and run. Here I checked It works as expected.
Video explaination below