[SOLVED] [QtSql] Create and configure a QTableView with Qt Creator

? Offline

This should fix it:

@model->setQuery(sql,DB); // DB is your QSqlDatabase object@

? Offline

[quote author="HuXiKa" date="1307969159"]This should fix it:

@model->setQuery(sql,DB); // DB is your QSqlDatabase object@[/quote]

I'm not sure where you want me to put this. As I understand it, the db variable I used in my header connection.h is a local variable, and can't be used in another function.

So what do I write in db? I tried including connection.h in mainwindow.cpp, but it didn't help.

Thanks!

? Offline

When you create database, if you provide a name, that could be passed in this call to get the db.

@
QSqlDatabase db = QSqlDatabase::database("QPSQL"); // like in your destructor
@

But, when you call setQuery without the db argument, it uses
@
void QSqlQueryModel::setQuery ( const QString & query, const QSqlDatabase & db = QSqlDatabase() )
@

the default QSqlDatabase constructor creates an invalid database.

From Documentation

bq. QSqlDatabase::QSqlDatabase ()
Creates an empty, invalid QSqlDatabase object. Use addDatabase(), removeDatabase(), and database() to get valid QSqlDatabase objects.

? Offline

Ok. So I edited the line setQuery to become:

@model->setQuery("SELECT * FROM v_EmpAff", QSqlDatabase::database());@

However, my tableView still is empty.

? Offline

Hehe... you are still missing something, try giving the db name too.

If you create database using @QSqlDatabase::addDatabase("MyDB");@

access it using @QSqlDatabase::database("MyDB");@

If it still doesn't work, could be some other problem in querying the data. The table view itself will work correctly.

[Edit: "SELECT * FROM ""v_EmpAff""" -- Too many quotes?? If you need quotes in the string.. use " (\ being the escape character)..
should be setQuery("SELECT * FROM v_EmpAff") or setQuery("SELECT * FROM "v_EmpAff"").. don't need the quotes there in SQL as far as i know..]

? Offline

Still doesn't work. I'm reposting my most recent files.

This is my connection.h

@#ifndef CONNECTION_H
#define CONNECTION_H

#include <QMessageBox>
#include <QtSql>

/* Création d'une connection à la BD
"qaimagerie", source des données
pour l'interface. */

static bool createConnection()
{
QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL", "qaimagerie"); // Définition du driver

// Set db name, username and password to access DB
db.setDatabaseName("qaimagerie");
db.setUserName("*****");
db.setPassword("*****");

// Displays error if database connection fails
if(!db.open())
{
    QMessageBox::critical(0, QObject::tr("Erreur de connection à la base de données"),
                          db.lastError().text());
    return false;
}
return true;

}

#endif // CONNECTION_H
@

And my mainwindow.cpp:

@#include "mainwindow.h"
#include "ui_mainwindow.h"

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

QSqlQueryModel *model = new QSqlQueryModel;
model->setQuery("SELECT * FROM ""v_EmpAff""", QSqlDatabase::database("qaimagerie"));
model->setHeaderData(0, Qt::Horizontal, tr("Nom"));
model->setHeaderData(1, Qt::Horizontal, tr("Prénom"));
model->setHeaderData(2, Qt::Horizontal, tr("Abbr."));
model->setHeaderData(3, Qt::Horizontal, tr("Affiliation"));

ui->tableView->setModel(model);

}

MainWindow::~MainWindow()
{
QSqlDatabase db = QSqlDatabase::database();
db.close();

delete ui;

}
@

As I understand it, when I add the DB with

@QSqlDatabase::addDatabase("QPSQL", "qaimagerie");@

I'm identifying the driver "QPSQL" and defining a connection name, right?

The SQL code queries an existing view in my DB, I have checked. What could be wrong?

? Offline

[quote author="jim_kaiser" date="1307971155"]Hehe... you are still missing something, try giving the db name too.

If you create database using @QSqlDatabase::addDatabase("MyDB");@

access it using @QSqlDatabase::database("MyDB");@

If it still doesn't work, could be some other problem in querying the data. The table view itself will work correctly.

[Edit: "SELECT * FROM ""v_EmpAff""" -- Too many quotes?? If you need quotes in the string.. use " (\ being the escape character)..
should be setQuery("SELECT * FROM v_EmpAff") or setQuery("SELECT * FROM "v_EmpAff"").. don't need the quotes there in SQL as far as i know..][/quote]

YES! YOU RULE! I thought I needed double quotes, because when I queried the DB using pure SQL, it complained about my capitalization and I had to make use of double quotes.

THANKS! I've been at it for a couple of hours, only for stupid double quotes!

On the other hand, sorting does not seem to work, but my view already specifies an ordering scheme, so I guess that's why it doesn't work.

? Offline

My bad, the first argument to addDatabase is the connection type and second is the name. You have that correct. You want to use PostgreSQL right? I have to test it myself to check. Can test the code with Mysql.

I still don't understand how this works

@
model->setQuery("SELECT * FROM ""v_EmpAff""", QSqlDatabase::database("qaimagerie"));
@

the first argument, is effectively "SELECT * FROM " "v_EmpAff" "" (3 strings)

Anyways, i will test your code and let you know whats wrong.

[Edit: Thanks, and yeah the quotes caught my eye. Not sure about the sorting and all though :P]

? Offline

No, it's okay. It's working now.

Thanks a lot for your time!

? Offline

Thats great :) Glad to help. Could you edit the title and put [Solved] in it. That's the general flow around here.

Happy hacking!