Indexed DB delete row

gistfile1.js

function deleteRow(key) {
  	key = Number(key); // set as number - required to work
		store = getObjectStore(DB_TABLE_NAME, 'readwrite'); // get the object store allowing read and write
		var req = store.get(key);  // get row from table
		req.onsuccess = function(evt) { // success - able to get the row from the table
			var record = evt.target.result;
			if (typeof record == 'undefined') { // row is empty
				displayActionFailure("No record found");
				return;
			}
			req = store.delete(key); // delete row
			req.onsuccess = function(evt) { // success - display table columns
				displayRows(store);
			};
			req.onerror = function (evt) { // fail - display error
				console.error("deleteRow:", evt.target.errorCode);
			};
		};
		req.onerror = function (evt) { // fail - could not select row from key
			console.error("deleteRow:", evt.target.errorCode);
		};
	}