Windows下Qt连接MySql数据库

void UserData::Link()
{
    QSqlDatabase db=QSqlDatabase::addDatabase("QMYSQL");
    db.setPort(3306);
    db.setHostName("127.0.0.1");
    db.setDatabaseName("chat");
    db.setUserName("root");
    db.setPassword("admin");
    if(!db.open()){
        qDebug()<<"Unable to open database";
    }else{
        qDebug()<<"Database connection established";
    }
    db.exec("SET NAMES GBK");
}