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QSqlDatabase common problem

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  • X Offline
    X Offline
    xeroblast
    wrote on last edited by
    #1

    why do i get this error : QSqlDatabasePrivate::addDatabase: duplicate connection name 'qt_sql_default_connection', old connection removed.

    i already follow what's in the docs...

    @
    window::window()
    {
    {
    db = QSqlDatabase::addDatabase("QMYSQL");
    // query here
    query.clear();
    db.close();
    }
    QSqlDatabase.removeDatabase("QMYSQL");
    }
    @

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    • I Offline
      I Offline
      Immii
      wrote on last edited by
      #2

      http://doc.trolltech.com/4.2/qsqldatabase.html#addDatabase

      can you check with this if DB is still open?
      bool db.isOpen()
      QDatabase::removeDatabase("databaseName");

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      • I Offline
        I Offline
        Immii
        wrote on last edited by
        #3

        u can try try using connection name when you add your DB and see

        QSqlDatabase db = QSqlDatabase::database("your connection name");

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        • I Offline
          I Offline
          Immii
          wrote on last edited by
          #4

          i just found this "thread":http://developer.qt.nokia.com/forums/viewthread/328/

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          • X Offline
            X Offline
            xeroblast
            wrote on last edited by
            #5

            it is close running a db.isOpen()...

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            • X Offline
              X Offline
              xeroblast
              wrote on last edited by
              #6

              i limit the error by doing something like this

              @
              window::window() {
              QString conn = db.connectionName();
              if (conn.isEmpty()) {
              db = QSqlDatabase::addDatabase("QMYSQL");
              }
              }
              window::close() {
              QSqlDatabase::removeDatabase("QMYSQL");
              }
              @

              but this is not enough coz tha last query still displays the error coz the dbase is not remove...

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              • A Offline
                A Offline
                andre
                wrote on last edited by
                #7

                [quote author="xeroblast" date="1293007954"]but this is not enough coz tha last query still displays the error coz the dbase is not remove...[/quote]

                Off topic: could you try to write normal English please? "coz" "tha" etc. do not qualify. That would make your comments much easier to read. Thank you.

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                • X Offline
                  X Offline
                  xeroblast
                  wrote on last edited by
                  #8

                  im sorry...

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