QT6 SQLite and QSqlQuery "Parameter count mismatch" Error

Meskaz285

I wrote this function to add data to a database:

void MainWindow::save1() {
QString stid,stname,stsur,stage,stgen,stbday,stcourses;
stid=ui->Stid->text();
stname=ui->name->text();
stsur=ui->surname->text();
stage=ui->age->text();
if(ui->male->isChecked())
stgen="male";
if(ui->female->isChecked())
stgen="female";
stbday=ui->birthday->text();
stcourses=ui->courses->text();
QSqlQuery qry;
qry.prepare("INSERT INTO Student (Student ID,Name,Surname,Age,Gender,Birthday,Courses) VALUES "
"(:stid,:stname,:stsur,:stage,:stgen,:stbday,:stcourses)");
qry.bindValue(":stid", stid);
qry.bindValue(":stname",stname);
qry.bindValue(":stsur",stsur);
qry.bindValue(":stage",stage);
qry.bindValue(":stgen",stgen);
qry.bindValue(":stbday",stbday);
qry.bindValue(":stcourses",stcourses);
qry.exec();
}

I keep getting QSqlError("", "Parameter count mismatch", "").
I tried to find a solution but had no luck. I would like some help here

jsulm

@Meskaz285 said in QT6 SQLite and QSqlQuery "Parameter count mismatch" Error:

Student ID

You seem to have a space between Student and ID

Meskaz285

@jsulm that was how i named it in the db file. Should i not name it that way?

Chrisw01

@Meskaz285 You may need to wrap your names with a ` tick. I personally have had a lot of problems with bindValue so I switched to building the string to be executed.

e.g.:

         QString sqlString = QString("INSERT INTO Student(`Student ID`, `Name`, `Surname`, `Age`, `Gender`, `Birthday`, `Courses`) VALUES ('%1', '%2', '%3', '%4', '%5', '%6', '%7')").arg(stid).arg(stname).arg(stsur).arg(stage).arg(stgen).arg(stbday).arg(stcourses);

        success = false; errorCount = 0; // success is a bool and errorCount is a int.

        while((success = sql.exec(sqlString)) == false && (errorCount++ < 10)) {
            QTime dieTime = QTime::currentTime().addSecs(1);
            while(QTime::currentTime() < dieTime)
                QCoreApplication::processEvents(QEventLoop::AllEvents, 100);
        }
        if((errorCount > 0) && (success == false)) {
            // Handle your failure here
        }
        else {
         // handle your success here
        }

I have found this method to work best for me. I always had issues with bindValue and the second part of the code you may not need if you use a local sqlServer. I was having issues when using a remote server with sql.exec failing if the network conditions was not perfect.

Hope that helps...

JonB

@Meskaz285
Before you decide to follow @Chrisw01's route and abandon bindings in favour of literal inlines (which has its own issues), from where you are now you have only to try:

qry.prepare("INSERT INTO Student (`Student ID`,Name,Surname,Age,Gender,Birthday,Courses)

and the rest the same. You will always need to quote a column name which you have chosen to have a space in whenever you use it in SQL statements, e.g. when you get to your SELECT statements. And how you quote varies across SQL implementations. Up to you, but I wouldn't dream of choosing to have a space in a column name for the hassle :) Some people use underscore characters for that.

Meskaz285

@JonB Ah thank you. This worked for me