qtbase-opensource-src/examples/sql/connection.h

129 lines
5.7 KiB
C

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, 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 CONNECTION_H
#define CONNECTION_H
#include <QMessageBox>
#include <QSqlDatabase>
#include <QSqlError>
#include <QSqlQuery>
/*
This file defines a helper function to open a connection to an
in-memory SQLITE database and to create a test table.
If you want to use another database, simply modify the code
below. All the examples in this directory use this function to
connect to a database.
*/
//! [0]
static bool createConnection()
{
QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
db.setDatabaseName(":memory:");
if (!db.open()) {
QMessageBox::critical(nullptr, QObject::tr("Cannot open database"),
QObject::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 person (id int primary key, "
"firstname varchar(20), lastname varchar(20))");
query.exec("insert into person values(101, 'Danny', 'Young')");
query.exec("insert into person values(102, 'Christine', 'Holand')");
query.exec("insert into person values(103, 'Lars', 'Gordon')");
query.exec("insert into person values(104, 'Roberto', 'Robitaille')");
query.exec("insert into person values(105, 'Maria', 'Papadopoulos')");
query.exec("create table items (id int primary key,"
"imagefile int,"
"itemtype varchar(20),"
"description varchar(100))");
query.exec("insert into items "
"values(0, 0, 'Qt',"
"'Qt is a full development framework with tools designed to "
"streamline the creation of stunning applications and "
"amazing user interfaces for desktop, embedded and mobile "
"platforms.')");
query.exec("insert into items "
"values(1, 1, 'Qt Quick',"
"'Qt Quick is a collection of techniques designed to help "
"developers create intuitive, modern-looking, and fluid "
"user interfaces using a CSS & JavaScript like language.')");
query.exec("insert into items "
"values(2, 2, 'Qt Creator',"
"'Qt Creator is a powerful cross-platform integrated "
"development environment (IDE), including UI design tools "
"and on-device debugging.')");
query.exec("insert into items "
"values(3, 3, 'Qt Project',"
"'The Qt Project governs the open source development of Qt, "
"allowing anyone wanting to contribute to join the effort "
"through a meritocratic structure of approvers and "
"maintainers.')");
query.exec("create table images (itemid int, file varchar(20))");
query.exec("insert into images values(0, 'images/qt-logo.png')");
query.exec("insert into images values(1, 'images/qt-quick.png')");
query.exec("insert into images values(2, 'images/qt-creator.png')");
query.exec("insert into images values(3, 'images/qt-project.png')");
return true;
}
//! [0]
#endif