javascript - transaction.executeSql Success function error -

i did function select data db , show alert, i'm getting following error in success function:

cannot read property 'rows' of undefined retrievedata

here functions

 function selectall(){     db.transaction( function(transaction) {     transaction.executesql("select * cdprodutos", [], retrievedata()); //the retrievedata function data sent/returned in parameters (transation, results) }); } function retrievedata(transaction, results) {    for(var = 0; < results.rows.length; i++) {          var data = results.rows.item(i)['id']         alert(data.value);     } } 

it looks function being executed , there no data being passed it, rows property coming undefined. writing () after retrievedata, invoking function immediately. remove () use callback.

it appears need pass data along it, anonymous function trick here:

function selectall(){     db.transaction(         function(transaction) {             transaction.executesql("select * cdprodutos", [], function() {                 retrievedata(transation, results); //not sure results comes from? parameter of function??         });     }); }  function retrievedata(transaction, results) {     for(var = 0; < results.rows.length; i++) {         var data = results.rows.item(i)['id']         alert(data.value);     } }