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  • Qt数据库2

    一、QSqlQueryModel

          The QSqlQueryModel class provides a read-only data model for SQL result sets.

           QSqlQueryModel is a high-level interface for executing SQL statements and traversing the result set. It is built on top of the lower-level QSqlQuery and can be used to provide data to view classes such as QTableView. For example:

    QSqlQueryModel *model = new QSqlQueryModel;
        model->setQuery("SELECT name, salary FROM employee");
        model->setHeaderData(0, Qt::Horizontal, tr("Name"));
        model->setHeaderData(1, Qt::Horizontal, tr("Salary"));
    
        QTableView *view = new QTableView;
        view->setModel(model);
        view->show();

    二、QSqlTableModel

      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(parentObject, database);
        model->setTable("employee");
        model->setEditStrategy(QSqlTableModel::OnManualSubmit);
        model->select();
        model->setHeaderData(0, Qt::Horizontal, tr("Name"));
        model->setHeaderData(1, Qt::Horizontal, tr("Salary"));
    
        QTableView *view = new QTableView;
        view->setModel(model);
        view->hideColumn(0); // don't show the ID
        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:

    QSqlQueryModel model;
        model.setQuery("SELECT * FROM employee");
        int salary = model.record(4).value("salary").toInt();
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  • 原文地址:https://www.cnblogs.com/wiessharling/p/2856408.html
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