insert data to database

[nix]

Your insert command was wrong. Try

// Add include QSqlQuery, QSqlError, QtDebug
void MainForm::creat_db()
{
  db = QSqlDatabase::addDatabase("QSQLITE");
  #ifdef Q_OS_LINUX
  // store database file into user home folder in Linux
  QString path(QDir::home().path());
  path.append(QDir::separator()).append("my.db.sqlite");
  path = QDir::toNativeSeparators(path);
  db.setDatabaseName(path);
  #else
  // file exists in the application private folder
  db.setDatabaseName("my.db.sqlite");
  #endif
  // Open databasee
  if(!db.open())
  {
      QMessageBox::warning(0, QObject::tr("database error"),db.lastError().text());
  }
 
  QSqlQuery query;
  if ( ! query.exec("create table db_table "
                  "(id integer primary key, "
                  "start_time varchar(20), "
                  "decription varchar(30), "
                 "finish_time varchar(20));"))
  {
    qDebug() << query.lastError().text();
  }
 }
 
int MainForm::insert_to_db(QString start_time, QString description, QString finish_time)
 {
 int newId = -1;
 bool ret = false;
 if (db.isOpen())
 {
 // NULL = is the keyword for the autoincrement to generate next value
 QSqlQuery query;
 ret = query.exec(QString("insert into db_table(start_time, decription, finish_time)  values('%1','%2','%3');")
                  .arg(start_time).arg(description).arg(finish_time));
 // Get database given autoincrement value
 if (ret)
 {
 newId = query.lastInsertId().toInt();
 }
 else
 {
   qDebug() << query.lastError().text();
 }
 }
 return newId;
 }

// Add include QSqlQuery, QSqlError, QtDebug
void MainForm::creat_db()
{
  db = QSqlDatabase::addDatabase("QSQLITE");
  #ifdef Q_OS_LINUX
  // store database file into user home folder in Linux
  QString path(QDir::home().path());
  path.append(QDir::separator()).append("my.db.sqlite");
  path = QDir::toNativeSeparators(path);
  db.setDatabaseName(path);
  #else
  // file exists in the application private folder
  db.setDatabaseName("my.db.sqlite");
  #endif
  // Open databasee
  if(!db.open())
  {
      QMessageBox::warning(0, QObject::tr("database error"),db.lastError().text());
  }

  QSqlQuery query;
  if ( ! query.exec("create table db_table "
                  "(id integer primary key, "
                  "start_time varchar(20), "
                  "decription varchar(30), "
                 "finish_time varchar(20));"))
  {
    qDebug() << query.lastError().text();
  }
 }

int MainForm::insert_to_db(QString start_time, QString description, QString finish_time)
 {
 int newId = -1;
 bool ret = false;
 if (db.isOpen())
 {
 // NULL = is the keyword for the autoincrement to generate next value
 QSqlQuery query;
 ret = query.exec(QString("insert into db_table(start_time, decription, finish_time)  values('%1','%2','%3');")
                  .arg(start_time).arg(description).arg(finish_time));
 // Get database given autoincrement value
 if (ret)
 {
 newId = query.lastInsertId().toInt();
 }
 else
 {
   qDebug() << query.lastError().text();
 }
 }
 return newId;
 }

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You can replace the qDebug() by messagebox.

[vanduongbk]

thank you nix very much ,my problem was solve
if i create a result form , and result form is child form of mainform , on mainform have result button to open a result form
i have measurement and write data to a database in mainform ,
in result form ,i have creat a qtablewidget to display data, how i can display all data form database to this qtablewidget
thank for help

[ChrisW67]

QTableView and QSqlTableModel or QSqlQueryModel.

[vanduongbk]

hello
how i can create many table in database ,sample as db1_table ,db2_table ....
and how i can write a insert function to each dbn_table
i use qtablewidget ,how when a record was insert to db ,it is also simultaneously display on qtablewidget
plz me ,thank

[vanduongbk]

hi ChrisW67
i have write a code in result form as below to display the data from a database but when compile ,it appear error:

C2248: 'QTableWidget::setModel' : cannot access private member declared in class 'QTableWidget'
see declaration of 'QTableWidget::setModel'
see declaration of 'QTableWidget'

QSqlQueryModel *model=new QSqlQueryModel;
    model->setQuery("SELECT start_time,description,finish_time FROM db_table");
    model->setHeaderData(0,Qt::Horizontal,tr("start_time"));
    model->setHeaderData(1,Qt::Horizontal,tr("description"));
    model->setHeaderData(1,Qt::Horizontal,tr("finish_time"));
 
    ui->tableWidget_1->setModel(model);
    ui->tableWidget_1->show();

QSqlQueryModel *model=new QSqlQueryModel;
    model->setQuery("SELECT start_time,description,finish_time FROM db_table");
    model->setHeaderData(0,Qt::Horizontal,tr("start_time"));
    model->setHeaderData(1,Qt::Horizontal,tr("description"));
    model->setHeaderData(1,Qt::Horizontal,tr("finish_time"));

    ui->tableWidget_1->setModel(model);
    ui->tableWidget_1->show();

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[nix]

Because you want use QTableView instead of QTableWidget.

[vanduongbk]

hi nix
this mean that i can not use QTableWidget for display data ,only can use QTableView ?

[nix]

If you want use a table with a model use QTableView if you want to insert your data by yourself use QTableWidget. Read the doc about those two classes and about Model/View programming

[vanduongbk]

hi nix
how i can call data from database in mainform and display this database on result form

[nix]

Your code using a model was not so far try this
http://doc.qt.io/qt-4.8/qsqltablemodel.html/#details

[vanduongbk]

my problem is solve
thank you

[vanduongbk]

hello
i have record to database and display well on qtable
but i have a question how the lastest record data to database is the first display on table

[BalaQT]

Use order by clause

model->setQuery("SELECT start_time,description,finish_time FROM db_table [B]order by id desc[/B]");

model->setQuery("SELECT start_time,description,finish_time FROM db_table [B]order by id desc[/B]");

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hope it helps,
bala