Qt 5.11 | Qt SQL | Master Detail Example | database.h Example File

Qt 5.11.3 Reference Documentation

# database.h Example File

masterdetail/database.h

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      #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(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 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\xc3\xb8r', 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