Qt Reference Documentation

- Qt 4.8
- ALL VERSIONS

- A
- A
- A
- Print

# database.h Example File

sql/masterdetail/database.h

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** 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 The Qt Company Ltd 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."
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #ifndef DATABASE_H
     #define DATABASE_H

     #include <QMessageBox>
     #include <QSqlDatabase>
     #include <QSqlError>
     #include <QSqlQuery>

     static bool createConnection()
     {
         QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
         db.setDatabaseName(":memory:");
         if (!db.open()) {
             QMessageBox::critical(0, qApp->tr("Cannot open database"),
                 qApp->tr("Unable to establish a database connection.\n"
                          "This example needs SQLite support. Please read "
                          "the Qt SQL driver documentation for information how "
                          "to build it.\n\n"
                          "Click Cancel to exit."), QMessageBox::Cancel);
             return false;
         }

         QSqlQuery query;

         query.exec("create table artists (id int primary key, "
                                          "artist varchar(40), "
                                          "albumcount int)");

         query.exec("insert into artists values(0, '<all>', 0)");
         query.exec("insert into artists values(1, 'Ane Brun', 2)");
         query.exec("insert into artists values(2, 'Thomas Dybdahl', 3)");
         query.exec("insert into artists values(3, 'Kaizers Orchestra', 3)");

         query.exec("create table albums (albumid int primary key, "
                                          "title varchar(50), "
                                          "artistid int, "
                                          "year int)");

         query.exec("insert into albums values(1, 'Spending Time With Morgan', 1, "
                            "2003)");
         query.exec("insert into albums values(2, 'A Temporary Dive', 1, 2005)");
         query.exec("insert into albums values(3, '...The Great October Sound', 2, "
                            "2002)");
         query.exec("insert into albums values(4, 'Stray Dogs', 2, 2003)");
         query.exec("insert into albums values(5, "
             "'One day you`ll dance for me, New York City', 2, 2004)");
         query.exec("insert into albums values(6, 'Ompa Til Du D\xf8r', 3, 2001)");
         query.exec("insert into albums values(7, 'Evig Pint', 3, 2002)");
         query.exec("insert into albums values(8, 'Maestro', 3, 2005)");

         return true;
     }

     #endif