database.h

#ifndef DATABASE_H
#define DATABASE_H

#include <QTextCodec>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QTime>
#include <QSqlError>
#include <QtDebug>
#include <QSqlDriver>
#include <QSqlRecord>

class DataBase
{
public:
    bool
 
 createConnection();  //建立一個連線
    bool createTable();       //建立資料庫表
    bool insert();            //出入資料
    bool queryAll();          //查詢所有資訊
    bool updateById(int id);  //更新
    bool deleteById(int id);  //刪除
    bool sortById();          //排序
};

#endif // DATABASE_H

database.cpp

#include "database.h"


//建立一個數據庫連線
bool DataBase::createConnection()
{
    //
 
以後就可以用"sqlite1"與資料庫進行連線了
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", "sqlite1");
    db.setDatabaseName(".//qtDb.db");
    if( !db.open())
    {
        qDebug() << "無法建立資料庫連線";
        return false;
    }
    return true;
}

//建立資料庫表
bool DataBase::createTable()
{
    QSqlDatabase db = QSqlDatabase::database("sqlite1"
 
); //建立資料庫連線
    QSqlQuery query(db);
    bool success = query.exec("create table automobil(id int primary key,attribute varchar,"
                              "type varchar,kind varchar,nation int,carnumber int,elevaltor int,"
                              "distance int,oil int,temperature int)");
    if(success)
    {
        qDebug() << QObject::tr("資料庫表建立成功！\n");
        return true;
    }
    else
    {
        qDebug() << QObject::tr("資料庫表建立失敗！\n");
        return false;
    }
}

//向資料庫中插入記錄
bool DataBase::insert()
{
    QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立資料庫連線
    QSqlQuery query(db);
    query.prepare("insert into automobil values(?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

    long records = 10;
    for(int i=0; i<records; i++)
    {
        query.bindValue(0, i);
        query.bindValue(1, "四輪");
        query.bindValue(2, "轎車");
        query.bindValue(3, "富康");
        query.bindValue(4, rand()%100);
        query.bindValue(5, rand()%10000);
        query.bindValue(6, rand()%300);
        query.bindValue(7, rand()%200000);
        query.bindValue(8, rand()%52);
        query.bindValue(9, rand()%100);

        bool success=query.exec();
        if(!success)
        {
            QSqlError lastError = query.lastError();
            qDebug() << lastError.driverText() << QString(QObject::tr("插入失敗"));
            return false;
        }
    }
    return true;
}

//查詢所有資訊
bool DataBase::queryAll()
{
    QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立資料庫連線
    QSqlQuery query(db);
    query.exec("select * from automobil");
    QSqlRecord rec = query.record();
    qDebug() << QObject::tr("automobil表字段數：" ) << rec.count();

    while(query.next())
    {
        for(int index = 0; index < 10; index++)
            qDebug() << query.value(index) << " ";
        qDebug() << "\n";
    }
}

//根據ID刪除記錄
bool DataBase::deleteById(int id)
{
    QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立資料庫連線
    QSqlQuery query(db);
    query.prepare(QString("delete from automobil where id = %1").arg(id));
    if(!query.exec())
    {
        qDebug() << "刪除記錄失敗！";
        return false;
    }
    return true;
}

//根據ID更新記錄
bool DataBase::updateById(int id)
{
    QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立資料庫連線
    QSqlQuery query(db);
    query.prepare(QString("update automobil set attribute=?,type=?,"
                             "kind=?, nation=?,"
                             "carnumber=?, elevaltor=?,"
                             "distance=?, oil=?,"
                             "temperature=? where id=%1").arg(id));

     query.bindValue(0,"四輪");
     query.bindValue(1,"轎車");
     query.bindValue(2,"富康");
     query.bindValue(3,rand()%100);
     query.bindValue(4,rand()%10000);
     query.bindValue(5,rand()%300);
     query.bindValue(6,rand()%200000);
     query.bindValue(7,rand()%52);
     query.bindValue(8,rand()%100);

     bool success=query.exec();
     if(!success)
     {
          QSqlError lastError = query.lastError();
          qDebug() << lastError.driverText() << QString(QObject::tr("更新失敗"));
     }
    return true;
}

//排序
bool DataBase::sortById()
{
    QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立資料庫連線
    QSqlQuery query(db);
    bool success=query.exec("select * from automobil order by id desc");
    if(success)
    {
        qDebug() << QObject::tr("排序成功");
        return true;
    }
    else
    {
        qDebug() << QObject::tr("排序失敗！");
        return false;
    }
}

main.cpp

#include <QCoreApplication>
#include "database.h"

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    QTextCodec::setCodecForLocale(QTextCodec::codecForLocale());

    DataBase d;
    d.createConnection();  //建立連線
    //d.createTable();
    //d.insert();
    d.queryAll();          //已經完成過createTable(), insert(), 現在進行查詢

    return 0;
}

執行結果

專案名稱為”sqlex”，然後就可以在與當前專案同一級目錄下的“build-SQLEx-Desktop_Qt_5_7_0_MinGW_32bit-Debug”中可以看到qtDb.db資料庫檔案，該資料庫可以用軟體SQLite直接開啟