sqlite.cpp

本文件是＜精通QT4编程＞的配套源代码

#ifndef CONNECTION_H
#define CONNECTION_H

#include <QtCore>
#include <QMessageBox>
#include <QSqlDatabase>
#include <QSqlDriver>
#include <QSqlError>
#include <QSqlQuery>
#include <QSqlRecord>
#include <QStringList>
#include <iostream>
#include <QApplication>
#include <QTime>
#include <QVariant>
#include <QDebug>
#include <stdlib.h>

using namespace std;

int main(int argc, char *argv[])
{
	QDateTime date= QDateTime::fromString(QString("21.5.1990"), QString("d.M.yyyy"));
	QApplication app(argc, argv);
	QTextCodec::setCodecForTr(QTextCodec::codecForName("gb2312"));
  QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
  db.setDatabaseName(":memory:");
    if (!db.open()) {
        QMessageBox::critical(0, QObject::tr("无法打开数据库，请阅读Qt SQL驱动文档！\n"),
		QObject::tr("退出请按Cancel键"),
		 QMessageBox::Cancel, QMessageBox::NoButton);
        return false;
    }
    QSqlQuery query;
    bool bSuccess = 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(bSuccess)
		qDebug() << QObject::tr("数据库表创建成功！\n");
	else
		qDebug() << QObject::tr("数据库表创建失败！\n");

	query.exec("SELECT * FROM automobil");
	QSqlRecord rec = query.record();
	qDebug() << QObject::tr("automobil表字段数：" )<< rec.count();

	QTime t;
	srand(1);
	t.start();

	query.prepare("INSERT INTO automobil "
		"VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");
	long records = 10000;
	for(int i=0;i<records;i++) {
		query.bindValue(0, i);
		query.bindValue(1, "四轮");
		query.bindValue(2, "轿车");
		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);

		bSuccess = query.exec();
		if(!bSuccess) {
			QSqlError lastError = query.lastError();
			qDebug() << lastError.driverText()<<QString(QObject::tr("插入失败"));
		}
	}
	qDebug()<<QObject::tr("插入 %1条记录, 耗时: %2 ms").arg(records).arg(t.elapsed());
	t.restart();
	bSuccess = query.exec("SELECT * FROM automobil ORDER BY id DESC");
	if(bSuccess)
		qDebug()<<QObject::tr("排序 %1 条记录,  耗时: %2 ms").arg(records).arg(t.elapsed());
	else
		qDebug()<<QObject::tr("排序失败！");


	t.restart();
	for(int i=0;i<records;i++) {
	query.clear();
	query.prepare(QString("UPDATE automobil SET "
		"attribute=?, type=?, kind=?, "
		"nation=?, carnumber=?, elevaltor=?, "
		"distance=?, oil=?, temperature=? "
		"WHERE id=%1").arg(i));

		query.bindValue(0, "四轮");
		query.bindValue(1, "轿车");
		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);

		bSuccess = query.exec();
			if(!bSuccess) {
			QSqlError lastError = query.lastError();
			qDebug() << lastError.driverText()<<QString(QObject::tr("更新失败"));
		}
	}
	qDebug()<<QObject::tr("更新 %1条记录，耗时: %2 ms").arg(records).arg(t.elapsed());

	t.restart();
	query.exec("DELETE FROM automobil WHERE id=1500");
	qDebug()<<QObject::tr("删除一条记录，耗时： %1 ms").arg(t.elapsed());

  return 0;
}
#endif