updating data in sqlite database in titanium

/**
*   DBView.js
 */
var self = Ti.UI.currentWindow;
self.backgroundColor = '#333';
self.updateData = updateData;
// create view
var view = Ti.UI.createView();
var myFont = {fontSize: 18};

var cols = [20, 300];
var table = Ti.UI.createTableView();

updateData();

table.addEventListener("click", function(e){
Ti.API.info("row clicked with id: " + e.row.myIndex);
var win = Ti.UI.createWindow({
title: 'Update Data',
url:'/ui/common/UpdateData.js',
id:e.row.myIndex,
prevWindow:self
});
win.open();
});


view.add(table);
self.add(view);

function updateData(){
var tableData = [];


// get data
// install db in device
var db = Ti.Database.install('/mydata/mydb.sqlite', 'mydb');

var rows = db.execute('SELECT * FROM hello_tbl');
while (rows.isValidRow())
{

 var name = rows.fieldByName('name');
 var age = rows.fieldByName('age');
 var id = rows.fieldByName('id');
 Ti.API.info(name + ' ' + age);

 var tablerow = Ti.UI.createTableViewRow({
  className:'row',
  objName:'row',
  myIndex:id,
  height: 50
 });
 var label = Ti.UI.createLabel({text:name, font:myFont, left: cols[0]});
 var label2 = Ti.UI.createLabel({text:age, font:myFont, left: cols[1]});
 tablerow.add(label);
 tablerow.add(label2);
 tableData.push(tablerow);

 rows.next();
}
rows.close();

table.setData(tableData);
}


/**
*
*  UpdateData.js
 */

var self = Ti.UI.currentWindow;
self.backgroundColor = '#333';
// create view
var view = Ti.UI.createView();
var myFont = {fontSize: 18};
var myHeight = 50;
var myWidth = '80%';
var cols = [20, 300];
var rows = [20, 50, 120, 150, 220];

var db = Ti.Database.install('/mydata/mydb.sqlite', 'mydb');


var nameLbl = Ti.UI.createLabel({text:"Name: ", left:cols[0], top: rows[0], width:myWidth, font:myFont});
view.add(nameLbl);

var nameTxt = Ti.UI.createTextField({hintText :"Enter your name", left:cols[0], top: rows[1], width:myWidth, font:myFont});
view.add(nameTxt);

var ageLbl = Ti.UI.createLabel({text:"Age: ", left:cols[0], top: rows[2], width:myWidth, font:myFont});
view.add(ageLbl);

var ageTxt = Ti.UI.createTextField({hintText :"Enter your age", left:cols[0], top: rows[3], width:myWidth, font:myFont});
view.add(ageTxt);

var button = Ti.UI.createButton({title: 'Update Data', top: rows[4], left:cols[0], height:myHeight});
view.add(button);

button.addEventListener('click', function(e){
// get data
// install db in device


var rows = db.execute('UPDATE hello_tbl SET name = ?, age=? WHERE id = ?',
nameTxt.value, ageTxt.value, self.id);
Ti.API.info("data updated: " + nameTxt.value + " , " + ageTxt.value);

self.close();

self.prevWindow.updateData();
});

// populate data into UI
var rows = db.execute('SELECT * FROM hello_tbl WHERE id=?', self.id);
if (rows.isValidRow())
{
nameTxt.value = rows.fieldByName('name');
ageTxt.value = rows.fieldByName('age');
}

self.add(view);