[solved][SQL] problem with extracting data

  • Hi, I have a data base called "logingdata" and table "logingids" with columns: "id", "username" and "password" and I have a problem while extracting the data. Here is my code:

    QString username, password;
    username = ui->lineLogin->text();
    password = ui->linePassword->text();
    QSqlQuery qry;
    if(qry.exec("SELECT * FROM employeeinfo WHERE username=" + username +" and password=" + password)){
        int count = 0;
        if(count == 1){
            PoZalogowaniu zalog;
            QMessageBox::information(this, "Fail", "Wrong login or password");

    The qry.exec() returns "false". Where is a problem ?

    When I changed it to a different table with identical structure except that a username and "password" were integers then it worked... Why ?

  • Try getting more information by calling the lastError()-method.

  • I typed in a login "killerman" and password"killerman" and i got an error:

    Unknown column 'killerman' in 'where clause' QMYSQL: unable to execute query

  • Lifetime Qt Champion


    IIRC it should rather be something like:

    QString("SELECT * FROM employeeinfo WHERE username='%1' and password='%2'").arg(username, password)

    The quotes are missing from your original query

  • Thanks a lot :)

  • Lifetime Qt Champion

    You're welcome !

    Since you have it working now, please update the thread title prepending [solved] so other forum users may know a solution has been found :)

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