How to get a list of columns and column types, in the selected table?

haifisch

How to get a list of columns and column types, in the selected table? And then dynamically add the column name to Label + add LineEdit or Spin Box, depending on the type of column. If the type of the column is Text - add LineEdit, if the type of integer - add Spin Box.

QHBoxLayout* Layout = new QHBoxLayout;
Layout->setSizeConstraint(QLayout::SetMaximumSize);
QSqlQuery* queryTow = new QSqlQuery(conn.mydb);
QString sqlQueryTow = QString("SELECT column_name,column_type FROM table_name=%1").arg(query->value(0).toString());
queryTow->prepare(sqlQueryTow);
queryTow->exec();

    while (queryTow->next()) {                
        QLabel *Label = new QLabel(this);                
        QString columnName = queryTow->value(0).toString();
        Label->setText(columnName);
        Layout->addWidget(Label);
        QString columnType = queryTow->value(1).toString();
        if(columnType="TEXT") {
           QLineEdit *LineEdit = new QLineEdit();
           Layout->addWidget(LineEdit);
        } else if (columnType="INTEGER") {
           QSpinBox *SpinBox = new QSpinBox(this);
           Layout->addWidget(SpinBox);
        }
    }

VRonin

You probably want QSqlTableModel + QTableView

mrjj

Hi
As @VRonin says, there are better ways to make something to edit the tables :)

Anyway, to get the schema you can use sqlite_master
http://www.sqlite.org/faq.html#q7
There are similar ways for other DBMS.

Depending on how exact you need it, you might also be able to use
http://doc.qt.io/qt-5/qvariant.html#canConvert-1
on queryTow->value(X) to check what type it can convert to.
This is however not optimal, but could work if u only look for int/text

Christian Ehrlicher

If you need the db table types, you can retrieve them via QSqlQuery::record() and then you have access to every column via QSqlRecord::field()/QSqlField::type()

haifisch

@VRonin What is the request to the database? To get the names of the columns and the types of columns in the selected table.

haifisch

@VRonin I use Sqlite.

Christian Ehrlicher

QSqlRecord also has a function to retrieve the column names ... http://doc.qt.io/qt-5/qsqlfield.html#name

haifisch

@Christian-Ehrlicher To use it you need to get a table with types and names. Let's say I know the name of the table. What query will allow to extract only the names and types of columns in the table?

Christian Ehrlicher

Then you should take a look at QSqlDatabase: http://doc.qt.io/qt-5/qsqldatabase.html#record
The documentation is your friend

JonB

@haifisch

What query will allow to extract only the names and types of columns in the table?

In addition to @Christian-Ehrlicher's http://doc.qt.io/qt-5/qsqlfield.html#name for the column names, see http://doc.qt.io/qt-5/qsqlfield.html#type for how the column type is stored at Qt-side. Or, did you want the actual, underlying SQL type?

haifisch

@JonB You can close the question. I already understood how to get a list of columns and column types in the selected table.