QT 与　MySQL 连接的问题

connection.h:

#ifndef CONNECTION_H
#define CONNECTION_H

#include <qsqldatabase.h>

inline bool createOneConnection()
{
QSqlDatabase *db;
db = QSqlDatabase::addDatabase("QMYSQL3");
db->setHostName("127.0.0.1");
db->setDatabaseName("qttest");
db->setUserName("root");
if (!db->open()) {
db->lastError().showMessage();
return false; }
return false;
}
return true;
}

#endif



main.cpp:

#include <qapplication.h>
#include <qsqldatabase.h>

#include "connection.h"

int main(int argc, char *argv[])
{
QApplication app(argc, argv);
if (createOneConnection())
return 1;

QSqlQuery query;
query.exec("CREATE TABLE artist ("
"id INTEGER PRIMARY KEY, "
"name VARCHAR(40) NOT NULL, "
"country VARCHAR(40))");
query.exec("CREATE TABLE cd ("
"id INTEGER PRIMARY KEY, "
"artistid INTEGER NOT NULL, "
"title VARCHAR(40) NOT NULL, "
"year INTEGER NOT NULL)");
query.exec("CREATE TABLE track ("
"id INTEGER PRIMARY KEY, "
"cdid INTEGER NOT NULL, "
"number INTEGER NOT NULL, "
"title VARCHAR(40) NOT NULL, "
"duration INTEGER NOT NULL)");

#if 1
query.exec("INSERT INTO artist "
"VALUES (1001, 'Gluecifer', 'Norway')");
query.exec("INSERT INTO artist "
"VALUES (1002, 'The Sounds', 'Sweden')");
query.exec("INSERT INTO artist "
"VALUES (1003, 'Melvins', 'USA')");
query.exec("INSERT INTO artist "
"VALUES (1004, 'Strapping Young Lads', 'Canada')");
query.exec("INSERT INTO cd "
"VALUES (2001, 1001, 'Riding the Tiger', 1997)");
query.exec("INSERT INTO cd "
"VALUES (2002, 1001, 'Easy Living', 2002)");
query.exec("INSERT INTO cd "
"VALUES (2003, 1002, 'Living in America', 2002)");
query.exec("INSERT INTO cd "
"VALUES (2004, 1003, 'Bullhead', 1991)");
query.exec("INSERT INTO cd "
"VALUES (2005, 1003, 'Stag', 1996)");
query.exec("INSERT INTO cd "
"VALUES (2006, 1003, 'Hostile Ambient Takeover', "
"2002)");
query.exec("INSERT INTO cd "
"VALUES (2007, 1003, '26 Songs', 2003)");
query.exec("INSERT INTO cd "
"VALUES (2008, 1004, 'City', 1997)");
query.exec("INSERT INTO cd "
"VALUES (2009, 1004, 'No Sleep Till Bedtime', "
"1998)");
query.exec("INSERT INTO cd "
"VALUES (2010, 1004, 'Syl', 2003)");
query.exec("INSERT INTO track "
"VALUES (3001, 2004, 01, 'Boris', 514)");
query.exec("INSERT INTO track "
"VALUES (3002, 2004, 02, 'Anaconda', 143)");
query.exec("INSERT INTO track "
"VALUES (3003, 2004, 03, 'Ligature', 229)");
query.exec("INSERT INTO track "
"VALUES (3004, 2004, 04, 'It''s Shoved', 155)");
query.exec("INSERT INTO track "
"VALUES (3005, 2004, 05, 'Zodiac', 254)");
query.exec("INSERT INTO track "
"VALUES (3006, 2004, 06, 'If I Had An Exorcism', "
"187)");
query.exec("INSERT INTO track "
"VALUES (3007, 2004, 07, 'Your Blessed', 339)");
query.exec("INSERT INTO track "
"VALUES (3008, 2004, 08, 'Cow', 271)");
#endif

return 0;
}



运行时弹出对话框：Driver not loaded Driver not loaded.

实在不知道是什么原因。

为什么ＱＴ与MySQl连不上呢？

在网上看到很多人问这个问题，可是没人答得出来，

还望高手不吝赐教．