search in a local database (sql) with AS3

I've got an AS3 code that goes to a php page on a website. That php search in a database (sql) online and send results to my AS3 code.

So I've got 3 files : my project (FLA file), my php file, and my sql file.

Everything is working, but now I would like to do this operation offline (local).

How can I do ?

In my AS3 code I've got :

var urlreq =newURLRequest("http://www.****.com/****/myPHP.php");
urlreq.method =URLRequestMethod.POST;  
var urlVars =newURLVariables();  
urlVars.theport ="New-York";
urlreq.data = urlVars;  
var loader:URLLoader=newURLLoader(urlreq);
loader.addEventListener(Event.COMPLETE, completed);
loader.dataFormat =URLLoaderDataFormat.VARIABLES;
loader.load(urlreq);

In my php :

$theport = $_POST['theport'];...

linked to a conn.php file :

$cfg_hote ='mys****.perso';
$cfg_base ='******';
$cfg_user ='*****';
$cfg_password ='****rhx';

And I've got an sql file uploaded at phpmyadmin.ovh.net

So now, how can I do this operation offline (local) ?

I've tried to change

var urlreq =newURLRequest("http://www.****.com/****/myPHP.php");

to

var urlreq =newURLRequest("myPHP.php");

But it can't find the database on local (sql file);

Thx for your help

EDIT

I've tried to add that to my AS3 code :

import flash.data.SQLConnection;
import flash.data.SQLMode;
import flash.events.SQLErrorEvent;
import flash.events.SQLEvent;
import flash.filesystem.File;  
var conn:SQLConnection=newSQLConnection();  
conn.addEventListener(SQLEvent.OPEN, openHandler);
conn.addEventListener(SQLErrorEvent.ERROR, errorHandler);  
// The database file is in the application storage directory 
var folder:File=File.applicationStorageDirectory;
var dbFile:File= folder.resolvePath("database.sql");  
conn.openAsync(dbFile,SQLMode.UPDATE);  

function openHandler(event:SQLEvent):void{
trace("the database opened successfully");
}  

function errorHandler(event:SQLErrorEvent):void{
trace("Error message:",event.error.message);
trace("Details:",event.error.details);
}

But it can't open the database.sql (trace output : Error #3125: Unable to open the database file)

Anyone see what i can do ?