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The QSqlTableModel class provides an editable data model for a single database table. More...
Inherits QSqlQueryModel.
Inherited by QSqlRelationalTableModel.
The QSqlTableModel class provides an editable data model for a single database table.
QSqlTableModel is a high-level interface for reading and writing database records from a single table. It is build on top of the lower-level QSqlQuery and can be used to provide data to view classes such as QTableView. For example:
QSqlTableModel *model = new QSqlTableModel;
model->setTable("employee");
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->select();
model->removeColumn(0); // don't show the ID
model->setHeaderData(0, Qt::Horizontal, tr("Name"));
model->setHeaderData(1, Qt::Horizontal, tr("Salary"));
QTableView *view = new QTableView;
view->setModel(model);
view->show();
We set the SQL table's name and the edit strategy, then we set up the labels displayed in the view header. The edit strategy dictates when the changes done by the user in the view are actually applied to the database. The possible values are OnFieldChange, OnRowChange, and OnManualSubmit.
QSqlTableModel can also be used to access a database programmatically, without binding it to a view:
QSqlTableModel model; model.setTable("employee"); QString name = model.record(4).value("name").toString();
The code snippet above extracts the salary field from record 4 in the result set of the query SELECT * from employee.
It is possible to set filters using setFilter, or modify the sort order using setSort. At the end, you must call select to populate the model with data.
The sql/tablemodel example illustrates how to use QSqlTableModel as the data source for a QTableView.
QSqlTableModel provides no direct support for foreign keys. Use the QSqlRelationalTableModel and QSqlRelationalDelegate if you want to resolve foreign keys.
The QSQLITE driver locks for updates until a select is finished. QSqlTableModel fetches data (QSqlQuery::fetchMore()) as needed; this may cause the updates to time out.
See also QSqlRelationalTableModel, QSqlQuery, Model/View Programming, Table Model Example, and Cached Table Example.
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