qt连接MySQL的问题

adaluobo

MySQL的驱动加载是成功的，而且MySQL本身也可以运行
但是测试程序运行显示连接失败
QApplication a(argc, argv);   
qDebug() << "Available drivers:";   
QStringList drivers = QSqlDatabase::drivers();
   foreach(QString driver, drivers)      
qDebug() << driver;
    //打开MySQL  
  QSqlDatabase data_base = QSqlDatabase::addDatabase("QMYSQL");
   data_base.setHostName("127.0.0.1");  //设置主机地址   
data_base.setPort(3306);  //设置端口   
data_base.setDatabaseName("MySQL57");  //设置数据库名称  
  data_base.setUserName("root");  //设置用户名   
data_base.setPassword("******");  //设置密码  
  if(!data_base.open())      
qDebug()<<"failed to connect to mysql";  
  else      
qDebug()<<"success";   
return a.exec();

输出显示：
Available drivers:
"QSQLITE"
"QMYSQL"
"QMYSQL3"
"QODBC"
"QODBC3"
"QPSQL"
"QPSQL7"
[SangforNsp] [GetCurOsVersion] Ver = 6.1
[SangforNsp]   NSPStartup[SangforNsp] [NSPStartup] Vista Or Later. User Ipv6 DNS Lookup Function.
[SangforNsp]   NSPStartup[SangforNsp] [NSPStartup] Vista Or Later. User Ipv6 DNS Lookup Function.
[SangforTcp] CSProxy refcount 34
[SangforTcp] Loading D:\maydayadagdbobbylyf\build-sqltest-Desktop_Qt_5_3_MinGW_32bit-Debug\debug\sqltest.exe...
[SangforTcp] WSPStartup ===> D:\maydayadagdbobbylyf\build-sqltest-Desktop_Qt_5_3_MinGW_32bit-Debug\debug\sqltest.exe[SangforTcp] [WSPStartup][UB_SSO]Current ProcessID = 18384[SangforTcp] 使用链式SPI[SangforTcp] [HandleSogou] GetModuleHandleEx Error 126![SangforTcp] WSPSocket===> 0 552[SangforTcp] [HELLO] zmm Socket Type ip 127.0.0.1 3306[SangforTcp] [WSPConnect]g_bQuit=0 g_ruleCount=0 g_port=0
[SangforTcp] [ForwardConnection]sockContext->rovider->NextProcTable.lpWSPConnect = 74415d85[SangforTcp] WSPCloseSocket fd=552 D:\maydayadagdbobbylyf\build-sqltest-Desktop_Qt_5_3_MinGW_32bit-Debug\debug\sqltest.exe
failed to connect to mysql