QT5 QSqlQuery的SELECT INSERT UPDATE DELETE命令用法

1.QSqlQuery的SELECT查詢記錄用法：

   QSqlQuery q("SELECT * FROM departments");
    QSqlRecord rec = q.record();

    int idCol = rec.indexOf("departID"); // index of the field "departID"
    int nameCol=rec.indexOf("department");// index of the field "department"
    
    QList<QString> listStrDepartID;//部門編號列表
    QList<QString> listStrDepartment;//部門名稱列表
    
    listStrDepartID.clear();//清空列表內容
    listStrDepartment.clear();//清空列表內容

    while (q.next())
    {
        listStrDepartID<<q.value(idCol).toString();//獲取表departments中的"departID"字段數據
        listStrDepartment<<q.value(nameCol).toString();//獲取表departments中的"department"字段數據
    }

2.QSqlQuery的INSERT插入記錄用法：

        QSqlQuery query;
        //新建departID記錄內容
        query.prepare("INSERT INTO departments (departID,department) "
                    "VALUES (:departID,:department)");
        query.bindValue(":departID",strNewDepartmentNum);
        query.bindValue(":department",ui->dbEditNewDepartmentName->text());
        query.exec();

3.QSqlQuery的UPDATE更新（或修改）記錄用法：

        QSqlQuery query;
        //更新departID處對應的department內容
        query.prepare("UPDATE  departments  SET department =:department WHERE departID =:departID ");

        query.bindValue(":departID",ui->dbEditModifyDepartmentNum->text());
        query.bindValue(":department",ui->dbComboModifyDepartmentName->currentText());
        query.exec();

4.QSqlQuery的DELETE刪除記錄用法：

        QSqlQuery query;
        //刪除departID記錄內容
        query.prepare("DELETE FROM departments WHERE departID =:departID ");

        query.bindValue(":departID",ui->dbEditDeleteDepartmentNum->text());
        query.exec();