Qt内置的QSQLITE数据库详解

database.h

 1 #ifndef DATABASE_H 2 #define DATABASE_H 3  4 #include <QTextCodec> 5 #include <QSqlDatabase> 6 #include <QSqlQuery> 7 #include <QTime> 8 #include <QSqlError> 9 #include <QtDebug>10 #include <QSqlDriver>11 #include <QSqlRecord>12 13 class DataBase14 {15 public:16     bool createConnection();  //创建一个连接17     bool createTable();       //创建数据库表18     bool insert();            //出入数据19     bool queryAll();          //查询所有信息20     bool updateById(int id);  //更新21     bool deleteById(int id);  //删除22     bool sortById();          //排序23 };24 25 #endif // DATABASE_H

database.cpp

  1 #include "database.h"  2   3   4 //建立一个数据库连接  5 bool DataBase::createConnection()  6 {  7     //以后就可以用"sqlite1"与数据库进行连接了  8     QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", "sqlite1");  9     db.setDatabaseName(".//qtDb.db"); 10     if( !db.open()) 11     { 12         qDebug() << "无法建立数据库连接"; 13         return false; 14     } 15     return true; 16 } 17  18 //创建数据库表 19 bool DataBase::createTable() 20 { 21     QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立数据库连接 22     QSqlQuery query(db); 23     bool success = query.exec("create table automobil(id int primary key,attribute varchar," 24                               "type varchar,kind varchar,nation int,carnumber int,elevaltor int," 25                               "distance int,oil int,temperature int)"); 26     if(success) 27     { 28         qDebug() << QObject::tr("数据库表创建成功！\n"); 29         return true; 30     } 31     else 32     { 33         qDebug() << QObject::tr("数据库表创建失败！\n"); 34         return false; 35     } 36 } 37  38 //向数据库中插入记录 39 bool DataBase::insert() 40 { 41     QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立数据库连接 42     QSqlQuery query(db); 43     query.prepare("insert into automobil values(?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"); 44  45     long records = 10; 46     for(int i=0; i<records; i++) 47     { 48         query.bindValue(0, i); 49         query.bindValue(1, "四轮"); 50         query.bindValue(2, "轿车"); 51         query.bindValue(3, "富康"); 52         query.bindValue(4, rand()%100); 53         query.bindValue(5, rand()%10000); 54         query.bindValue(6, rand()%300); 55         query.bindValue(7, rand()%200000); 56         query.bindValue(8, rand()%52); 57         query.bindValue(9, rand()%100); 58  59         bool success=query.exec(); 60         if(!success) 61         { 62             QSqlError lastError = query.lastError(); 63             qDebug() << lastError.driverText() << QString(QObject::tr("插入失败")); 64             return false; 65         } 66     } 67     return true; 68 } 69  70 //查询所有信息 71 bool DataBase::queryAll() 72 { 73     QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立数据库连接 74     QSqlQuery query(db); 75     query.exec("select * from automobil"); 76     QSqlRecord rec = query.record(); 77     qDebug() << QObject::tr("automobil表字段数：" ) << rec.count(); 78  79     while(query.next()) 80     { 81         for(int index = 0; index < 10; index++) 82             qDebug() << query.value(index) << " "; 83         qDebug() << "\n"; 84     } 85 } 86  87 //根据ID删除记录 88 bool DataBase::deleteById(int id) 89 { 90     QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立数据库连接 91     QSqlQuery query(db); 92     query.prepare(QString("delete from automobil where id = %1").arg(id)); 93     if(!query.exec()) 94     { 95         qDebug() << "删除记录失败！"; 96         return false; 97     } 98     return true; 99 }100 101 //根据ID更新记录102 bool DataBase::updateById(int id)103 {104     QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立数据库连接105     QSqlQuery query(db);106     query.prepare(QString("update automobil set attribute=?,type=?,"107                              "kind=?, nation=?,"108                              "carnumber=?, elevaltor=?,"109                              "distance=?, oil=?,"110                              "temperature=? where id=%1").arg(id));111 112      query.bindValue(0,"四轮");113      query.bindValue(1,"轿车");114      query.bindValue(2,"富康");115      query.bindValue(3,rand()%100);116      query.bindValue(4,rand()%10000);117      query.bindValue(5,rand()%300);118      query.bindValue(6,rand()%200000);119      query.bindValue(7,rand()%52);120      query.bindValue(8,rand()%100);121 122      bool success=query.exec();123      if(!success)124      {125           QSqlError lastError = query.lastError();126           qDebug() << lastError.driverText() << QString(QObject::tr("更新失败"));127      }128     return true;129 }130 131 //排序132 bool DataBase::sortById()133 {134     QSqlDatabase db = QSqlDatabase::database("sqlite1"); //建立数据库连接135     QSqlQuery query(db);136     bool success=query.exec("select * from automobil order by id desc");137     if(success)138     {139         qDebug() << QObject::tr("排序成功");140         return true;141     }142     else143     {144         qDebug() << QObject::tr("排序失败！");145         return false;146     }147 }

main.cpp

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 1 #include <QCoreApplication> 2 #include "database.h" 3  4 int main(int argc, char *argv[]) 5 { 6     QCoreApplication a(argc, argv); 7     QTextCodec::setCodecForLocale(QTextCodec::codecForLocale()); 8  9     DataBase d;10     d.createConnection();  //创建连接11     //d.createTable();12     //d.insert();13     d.queryAll();          //已经完成过createTable(), insert(), 现在进行查询14 15     return 0;16 }

运行结果

项目名称为”sqlex”，然后就可以在与当前项目同一级目录下的“
build-SQLEx-Desktop_Qt_5_7_0_MinGW_32bit-Debug”中可以看到qtDb.db数据库文件，该数据库可以用软件SQLite直接打开