MS SQL QODBC Query Size -1

[Pablik]

Hi, i have problem with MS SQL, after i open connection without error, all query i exec have size -1

void MainWindow::on_pushButtonLogin_clicked()
{
    QString nameServer = "192.168.3.201\\OPTIMA";
    QString dbName = "CDN_Test";
    QString dataBaseName = QString("DRIVER={SQL Server};SERVER=%1;DATABASE=%2;").arg(nameServer).arg(dbName);
 
    db = QSqlDatabase::addDatabase("QODBC");
    db.setDatabaseName(dataBaseName);
    db.setUserName("<LOGIN>");
    db.setPassword("<PASSWORD>");
 
    if (!db.open())
        QMessageBox::critical(0, QObject::tr("Database Error"), db.lastError().text());
}
 
void MainWindow::on_pushButtonGetUsers_clicked()
{
    QSqlQuery query(db);
    query.exec("SELECT * FROM [CDN].[Kontrahenci]");
 
    QMessageBox::critical(0, QObject::tr("Database Error"), query.lastError().text() );              //No error
    QMessageBox::critical(0, QObject::tr("Database Error"), QString::number( query.size() ));  // -1
 
}

void MainWindow::on_pushButtonLogin_clicked()
{
    QString nameServer = "192.168.3.201\\OPTIMA";
    QString dbName = "CDN_Test";
    QString dataBaseName = QString("DRIVER={SQL Server};SERVER=%1;DATABASE=%2;").arg(nameServer).arg(dbName);

    db = QSqlDatabase::addDatabase("QODBC");
    db.setDatabaseName(dataBaseName);
    db.setUserName("<LOGIN>");
    db.setPassword("<PASSWORD>");

    if (!db.open())
        QMessageBox::critical(0, QObject::tr("Database Error"), db.lastError().text());
}

void MainWindow::on_pushButtonGetUsers_clicked()
{
    QSqlQuery query(db);
    query.exec("SELECT * FROM [CDN].[Kontrahenci]");

    QMessageBox::critical(0, QObject::tr("Database Error"), query.lastError().text() );              //No error
    QMessageBox::critical(0, QObject::tr("Database Error"), QString::number( query.size() ));  // -1

}

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[Lesiok]

From QSqlQuery::size doc : Returns the size of the result (number of rows returned), or -1 if the size cannot be determined or if the database does not support reporting information about query sizes.

[Pablik]

So how i can get result of my query ??

[Lesiok]

I do not understand what the problem is. Size () == - 1 does not mean no result of query.

[Pablik]

Sorry i think if Szie() is -1 then next() and value() will by not work. Thx for help.
Is other way to check how meny record have query ???

I do someting like that, it work's but is not good way.

void MainWindow::on_pushButtonGetUsers_clicked()
{
 
 
    QSqlQuery query(db);
    query.exec("SELECT Knt_Kod, Knt_Ulica, Knt_NrDomu, Knt_Miasto, Knt_KodPocztowy, Knt_Poczta, Knt_Pesel FROM CDN.Kontrahenci");
    query.next();
    if(!query.value(0).toString().isEmpty())
    {
        ui->tableWidget->setRowCount(1);
        addRecordToTable(&query, 0);
        query.next();
 
        int row=2;
        while(!query.value(0).toString().isEmpty())
        {
            ui->tableWidget->setRowCount(row);
            addRecordToTable(&query, row-1);
            row++;
            query.next();
        }
    }
}

void MainWindow::on_pushButtonGetUsers_clicked()
{


    QSqlQuery query(db);
    query.exec("SELECT Knt_Kod, Knt_Ulica, Knt_NrDomu, Knt_Miasto, Knt_KodPocztowy, Knt_Poczta, Knt_Pesel FROM CDN.Kontrahenci");
    query.next();
    if(!query.value(0).toString().isEmpty())
    {
        ui->tableWidget->setRowCount(1);
        addRecordToTable(&query, 0);
        query.next();

        int row=2;
        while(!query.value(0).toString().isEmpty())
        {
            ui->tableWidget->setRowCount(row);
            addRecordToTable(&query, row-1);
            row++;
            query.next();
        }
    }
}

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[Lesiok]

Shorter code :

void MainWindow::on_pushButtonGetUsers_clicked()
{
 
 
    QSqlQuery query(db);
    query.exec("SELECT Knt_Kod, Knt_Ulica, Knt_NrDomu, Knt_Miasto, Knt_KodPocztowy, Knt_Poczta, Knt_Pesel FROM CDN.Kontrahenci");
    int row=1;
    while(query.next())
    {
            ui->tableWidget->setRowCount(row);
            addRecordToTable(&query, row-1);
            row++;
    }
}

void MainWindow::on_pushButtonGetUsers_clicked()
{


    QSqlQuery query(db);
    query.exec("SELECT Knt_Kod, Knt_Ulica, Knt_NrDomu, Knt_Miasto, Knt_KodPocztowy, Knt_Poczta, Knt_Pesel FROM CDN.Kontrahenci");
    int row=1;
    while(query.next())
    {
            ui->tableWidget->setRowCount(row);
            addRecordToTable(&query, row-1);
            row++;
    }
}

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BTW : why not to use QTableWidget with QSqlQuryModel ?