Retrieving database data to qtablewidget

Lasith

I am new to qt programming! I found a video tutorial in which data is being retireved to a qtableview! But since I am new model view programming seems to be bit complex! The following method is ueds to retrieve data to a qtableview(It works)!

void MainWindow::on_pushButton_4_clicked()
{
MainWindow conn;

    QSqlQueryModel * modal = new QSqlQueryModel();
    conn.connOpen();
    QSqlQuery* qry = new QSqlQuery(conn.mydb);
    qry->prepare("select user from usertable  where NAME='" +ui->textEdit->toPlainText()+ "'");
    qry->exec();
    modal->setQuery(*qry);
    ui->tableView_2->setModel(modal);

    conn.connClose();

}
conn is used to provide the database connection! How can I change the above method to retreive data to a qtablewidget?

jsulm

@Lasith Using QTableWidget would be even more complex as you would need to fill the table manually parsing the query result. But if you really want then see here: http://doc.qt.io/qt-5/qsqlquery.html

QSqlQuery query("SELECT country FROM artist");
while (query.next()) {
    QString country = query.value(0).toString();
    doSomething(country);
 }

With query.value(0) you get value of first column, with query.value(1) the value from second and so on. Use http://doc.qt.io/qt-5/qtablewidget.html#setItem to set each cell.

Lasith

@jsulm Thanx mate

karlheinzreichel

As in QTableWidget the setModel method is private you cannot use the model directly for setting data into a QTableWidget.

One possible solution would be that you add every single cell of the table as a QTableWidgetItem by hand.
In my opinion this solution would be more complex than working with models.

BTW: the code you posted as a sample is not really worth to mention.
e.g. every time you press your pushbutton4 a new model will be allocated and never released!

regards
Karl-Heinz

SGaist

Hi,

To add to @karlheinzreichel, there's no need to allocate QSqlQuery on the heap like you do. Just put it on the stack.

Richard Lee

You can use QSqlTableModel instead to do this.
//create a database object
QSqlDatabase db = QSqlDatabase::addDatabase(driver, name);
db.setDatabaseName(database_path);
db.open();

//bound the database to the QSqlTableModel
QSqlTableModel *model = new QSqlTableModel(this, db);
model.setTable(table_name);
model.select();

//Now you can retrieve data from the database via the model
QModelIndex idx = model.index(row, column);
model.data(idx);

For details, you can search the official reference online or in QtCreator:
Ctrl + K,
then type: ? QSqlTableModel.