Qsql and connection

[smemamian]

hi
I do not understand line 7 and 11,Please explain

#include <QCoreApplication>
#include <QtSql>
 
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    QString servername = "LOCALHOST\\SQLEXPRESS" ;
    QString dbname = "test";
    QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
    db.setConnectOptions();
    QString dsn = QString("DRIVER={SQL Native Client);SERVER=%1;DATABASE=%2;Trusted_Connection=Yes;").arg(servername).arg(dbname);
    db.setDatabaseName(dsn);
 
    return a.exec();
}

#include <QCoreApplication>
#include <QtSql>

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    QString servername = "LOCALHOST\\SQLEXPRESS" ;
    QString dbname = "test";
    QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
    db.setConnectOptions();
    QString dsn = QString("DRIVER={SQL Native Client);SERVER=%1;DATABASE=%2;Trusted_Connection=Yes;").arg(servername).arg(dbname);
    db.setDatabaseName(dsn);
    
    return a.exec();
}

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tnx

[alizadeh91]

Simply you are filling properties of db. servername is address or name of your server. because your computer is your own server so you have to use LOCALHOST or 127.0.0.1 for server name.

[ChrisW67]

The string you are constructing at Line 11 is a Data Source Name (DSN) which encapsulates a bunch of settings that you could, alternatively, set up in the Windows ODBC Manager. You should have a driver named "SQL Native Client" in the ODBC Manager.

Also, the line should read:

QString dsn = QString("DRIVER={SQL Native Client};SERVER=%1;DATABASE=%2;Trusted_Connection=Yes;").arg(servername).arg(dbname);

QString dsn = QString("DRIVER={SQL Native Client};SERVER=%1;DATABASE=%2;Trusted_Connection=Yes;").arg(servername).arg(dbname);

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Note a ')' became a '}'

[smemamian]

thanks a lot .

Why do I get the error message when I compile ?

QsqlDatabase: QODBC driver not loaded
QSqlDataase : available drivers:QSQLITE

my code :

#include <QCoreApplication>
#include <QtSql>
#include <QDebug>
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    QString servername = "LOCALHOST\\SQLEXPRESS" ;
    QString dbname = "test";
    QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
    db.setConnectOptions();
    QString dsn = QString("DRIVER={SQL Native Client};SERVER=%1;DATABASE=%2;Trusted_Connection=Yes;").arg(servername).arg(dbname);
    db.setDatabaseName(dsn);
 
    if(db.open())
    {
        qDebug() << "Opene.." ;
    }
 
    else
        qDebug() << "Not Opene.." << db.lastError();
 
    return a.exec();
}

#include <QCoreApplication>
#include <QtSql>
#include <QDebug>
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    QString servername = "LOCALHOST\\SQLEXPRESS" ;
    QString dbname = "test";
    QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
    db.setConnectOptions();
    QString dsn = QString("DRIVER={SQL Native Client};SERVER=%1;DATABASE=%2;Trusted_Connection=Yes;").arg(servername).arg(dbname);
    db.setDatabaseName(dsn);

    if(db.open())
    {
        qDebug() << "Opene.." ;
    }

    else
        qDebug() << "Not Opene.." << db.lastError();
    
    return a.exec();
}

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Microsoft SQL Server 2008
Windows 7