relationaltablemodel.cpp Example File

 /****************************************************************************
 **
 ** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
 ** Contact: http://www.qt-project.org/
 **
 ** This file is part of the examples of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:BSD$
 ** You may use this file under the terms of the BSD license as follows:
 **
 ** "Redistribution and use in source and binary forms, with or without
 ** modification, are permitted provided that the following conditions are
 ** met:
 **   * Redistributions of source code must retain the above copyright
 **     notice, this list of conditions and the following disclaimer.
 **   * Redistributions in binary form must reproduce the above copyright
 **     notice, this list of conditions and the following disclaimer in
 **     the documentation and/or other materials provided with the
 **     distribution.
 **   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
 **     the names of its contributors may be used to endorse or promote
 **     products derived from this software without specific prior written
 **     permission.
 **
 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
 **
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #include <QtWidgets>
 #include <QtSql>

 #include "../connection.h"

 void initializeModel(QSqlRelationalTableModel *model)
 {
     model->setTable("employee");

     model->setEditStrategy(QSqlTableModel::OnManualSubmit);
     model->setRelation(2, QSqlRelation("city", "id", "name"));
     model->setRelation(3, QSqlRelation("country", "id", "name"));

     model->setHeaderData(0, Qt::Horizontal, QObject::tr("ID"));
     model->setHeaderData(1, Qt::Horizontal, QObject::tr("Name"));
     model->setHeaderData(2, Qt::Horizontal, QObject::tr("City"));
     model->setHeaderData(3, Qt::Horizontal, QObject::tr("Country"));

     model->select();
 }

 QTableView *createView(const QString &title, QSqlTableModel *model)
 {
     QTableView *view = new QTableView;
     view->setModel(model);
     view->setItemDelegate(new QSqlRelationalDelegate(view));
     view->setWindowTitle(title);
     return view;
 }

 void createRelationalTables()
 {
     QSqlQuery query;
     query.exec("create table employee(id int primary key, name varchar(20), city int, country int)");
     query.exec("insert into employee values(1, 'Espen', 5000, 47)");
     query.exec("insert into employee values(2, 'Harald', 80000, 49)");
     query.exec("insert into employee values(3, 'Sam', 100, 1)");

     query.exec("create table city(id int, name varchar(20))");
     query.exec("insert into city values(100, 'San Jose')");
     query.exec("insert into city values(5000, 'Oslo')");
     query.exec("insert into city values(80000, 'Munich')");

     query.exec("create table country(id int, name varchar(20))");
     query.exec("insert into country values(1, 'USA')");
     query.exec("insert into country values(47, 'Norway')");
     query.exec("insert into country values(49, 'Germany')");
 }

 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
     if (!createConnection())
         return 1;
     createRelationalTables();

     QSqlRelationalTableModel model;

     initializeModel(&model);

     QTableView *view = createView(QObject::tr("Relational Table Model"), &model);
     view->show();

     return app.exec();
 }