QSqlError("", "Unable to fetch row", "No query")

[patcs]

Hi, I know that I have an error in commas but I can't find the error. Could someone help me, please?

This is my code:

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDebug>

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);

qDebug()<<"Aplicación inicializada...";

QString nombre;
nombre.append("baseDeDatos1.sqlite");
db = QSqlDatabase::addDatabase("QSQLITE");
db.setDatabaseName(nombre);

if(db.open()){
    qDebug()<<"Se ha conectado a la base de datos.";
}else{
    qDebug()<<"ERROR! NO se ha conectado a la base de datos.";
}

createUserTable();

}

MainWindow::~MainWindow()
{
delete ui;
}

void MainWindow::createUserTable()
{
QString consultation;
consultation.append("CREATE TABLE IF NOT EXISTS usuarios("
"id INTEGER PRIMARY KEY AUTOINCREMENT,"
"nombre VARCHAR(100),"
"primer_apellido VARCHAR(100),"
"segundo_apellido VARCHAR(100),"
"edad INTEGER NOT NULL"
");");

QSqlQuery create;
create.prepare(consultation);

if(create.exec())
{
    qDebug()<<"La tabla USUARIO existe o se ha creado correctamente.";

}else{
    qDebug()<<"La tabla USUARIO NO se ha creado correctamente.";
    qDebug()<<"ERROR!"<<create.lastError();

}

}

void MainWindow::InsertUser()
{

QString consultation;
consultation.append("INSERT INTO usuarios("
                    "nombre,"
                    "primer_apellido,"
                    "segundo_apellido,"
                    "edad)"
                    "VALUES("
                    "'"+ui->lineEditNombre->text()+"',"
                    "'"+ui->lineEditPrimerApellido->text()+"',"
                    "'"+ui->lineEditSegundoApellido->text()+"',"
                    ""+ui->lineEditEdad->text()+""
                    ");");

QSqlQuery insert;
insert.prepare(consultation);

if(insert.exec())
{
    qDebug()<<"El USUARIO se ha insertado correctamente.";

}else{
    qDebug()<<"La USUARIO NO se ha insertado correctamente.";
    qDebug()<<"ERROR!"<<insert.lastError();

}

}

void MainWindow::on_pushButtonAgregarUsuario_clicked()
{
InsertUser();
}

[SGaist]

Hi,

From a quick look you are missing the single quotes in your last parameter of consultation.

A cleaner solution would be to use a prepared query like described here.

[patcs]

Hi @SGaist , thank you for reply, but my last parameter is a INT so it shouldn't have a single quotes. Any way I tried but it doesn't work yet.

[SGaist]

Then you should also check what the generated query was. In any case, I still recommend using a prepared query. That will make your code cleaner and clearer.

[patcs]

@SGaist
How can I check what is the generated query? could you help me? I'm a beginner. Thanks a lot.

[patcs]

Please, someone can see my error??? I tried missing everything and it doesn't work.

[J.Hilk]

@patcs

QString consultation;
consultation.append("CREATE TABLE IF NOT EXISTS usuarios("
"id INTEGER PRIMARY KEY AUTOINCREMENT,"
"nombre VARCHAR(100),"
"primer_apellido VARCHAR(100),"
"segundo_apellido VARCHAR(100),"
"edad INTEGER NOT NULL"
");");

Last line thats ; should not be there

QString consultation;
consultation.append("CREATE TABLE IF NOT EXISTS usuarios("
"id INTEGER PRIMARY KEY AUTOINCREMENT,"
"nombre VARCHAR(100),"
"primer_apellido VARCHAR(100),"
"segundo_apellido VARCHAR(100),"
"edad INTEGER NOT NULL"
")");

[patcs]

Hi @J.Hilk I changed this, and the error it's the same...

[patcs]

I could, fix my error, I only have to delete my data base and build again. It works now.