hello i am have two grids and i transfer records from first grid (book with field: id, author,price) to second grid (discount with field: id, author, price, new price ) with drag and drop, all good, but i am want next: when i am drag record from grid (book) and drop to grid (discount) records with the same field "id" (that are in both tables) not inserted in grid (discount). I have an array of objects, how to make so that records with 'id' which is already in the table (discount) is not inserted. I am make :
listeners: {beforeDrop: function(node, data, overModel, dropPosition, dropHandlers) {}
but what write there ? thanks