qt连接MySql数据库及增删改查示例

#include "mainwindow.h"

#include "ui_mainwindow.h"

#include "QtSql/QSqlDatabase"

#include "QMessageBox"

#include "qdebug.h"

#include 

#include 

#include 

#include 

MainWindow::MainWindow(QWidget *parent) :

    QMainWindow(parent),

    ui(new Ui::MainWindow)

{

    ui->setupUi(this);

}

MainWindow::~MainWindow()

{

    delete ui;

}

void MainWindow::on_pushButton_clicked()

{

    QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");

        db.setHostName("127.0.0.1");

        db.setPort(3306);

        db.setDatabaseName("MyDataBaseName"); //不是Database,记得别填错

        db.setUserName("root");

        db.setPassword("root");

        bool ok = db.open();

        if (ok){

            QMessageBox::information(this, "infor", "link success");

        }

        else {

            QMessageBox::information(this, "infor", "link failed");

            qDebug()<<"error open database because"< 
  
        }
 
  
 
  
 
  
}
 
  
 
  
void MainWindow::on_pushButton_2_clicked()
 
  
{
 
  
    QSqlQuery query;
 
  
    QString sql1 = "create table ChannelValues1(id int ,name varchar(100),Ch1 double(64,5),Ch2 double(64,5));";
 
  
    query.exec(sql1);
 
  
}
 
  
 
  
void MainWindow::on_pushButton_3_clicked()
 
  
{
 
  
    QTime time;
 
  
    time.start();
 
  
    for(int i=0;i<500*10000;i++)
 
  
    {
 
  
        int id = 0;
 
  
        QString name = "aaa";
 
  
        double Ch1 = 9.999;
 
  
        double Ch2 = 8887.987666652;
 
  
        QString sql = QString("insert into ChannelValues1(id,name,Ch1,Ch2) values('%1','%2','%3','%4')").arg(id).arg(name).arg(Ch1).arg(Ch2);
 
  
        QSqlQuery query;
 
  
        query.exec(sql);
 
  
    }
 
  
  qDebug()<<"耗时"+time.elapsed()<<"毫秒";
 
  
}
 
  
 
  
void MainWindow::on_pushButton_4_clicked()
 
  
{
 
  
      int id =0;
 
  
       QString sql = QString("delete from ChannelValues1 where id = '%1'").arg(id);
 
  
       QSqlQuery query;
 
  
       query.exec(sql);
 
  
}
 
  
 
  
void MainWindow::on_pushButton_5_clicked()
 
  
{
 
  
        QSqlQuery q;
 
  
        q.exec("select *from ChannelValues1");
 
  
        while(q.next())   //遍历完为false
 
  
        {
 
  
            //以下标
 
  
            //qDebug()< 
  
           // < 
  
            //以字段
 
  
            qDebug()< 
  
            < 
  
        }
 
  
}
 
  
 
  
void MainWindow::on_pushButton_6_clicked()
 
  
{
 
  
    QSqlQuery query;
 
  
    QString sql1 = "DROP table ChannelValues1";
 
  
    query.exec(sql1);
 
  
}