Question

我在带有SQlite数据库的javaFx项目中使用JDBC。我有两个表"PROJECT"和"SMAllPROJECT"，例如PROJECT具有此结构PROJECT(name,date,state)而SMAllPROJECT具有此结构SMAllPROJECT(name,date,state,*project_name*)。 Project_name的{{1}}列引用了name。

我正在尝试从PROJECT table删除行，并且应删除PROJECT中引用的行。在sqlite studio中，当我从父表中删除一行时，我配置了SMAllPoject方法，当我在SQlite studio中测试时，每个东西都很好，但是在我的代码中，它只是从父表中删除了行。

这是我的代码：

控制器方法

onCascade

DAO模式方法

public void ExecuteDeleteProject() {

        if (!SearchIdProjectSupp.getText().isEmpty()) {

            Project project = new ProjectDao().FindString(SearchIdProjectSupp.getText());
            new ProjectDao().Delete(project);
            String title = "Suppression";
            String message = "Vous avez supprimé le projet " + SearchIdProjectSupp.getText() + ".";
            NotificationType notification = NotificationType.SUCCESS;
            TrayNotification tray = new TrayNotification();
            tray.setTitle(title);
            tray.setMessage(message);
            tray.setNotificationType(notification);
            tray.setAnimationType(AnimationType.SLIDE);
            tray.setImage(new Image("Images/check.png"));
            tray.setRectangleFill(Paint.valueOf("#a8a9fe"));
            tray.showAndDismiss(Duration.seconds(4));
            SearchIdProjectSupp.setText("");
            SuppPaneProject.setVisible(false);
            DeleteProjetButton.setDisable(true);
            CountP.setVisible(true);
            CountP();
            CountR();
            CountPP();

        }

    }

这是我的DDL

public boolean Delete(Project Object) {

        try {

            String queryDeletePerson = "DElETE FROM PROJECT WHERE name=" + "'" + Object.getName() + "'";//Query Insertion in Person_Table

            PreparedStatement preparedStatementPerson = Dbaconnection.getConnection().prepareStatement(queryDeletePerson);//Prepared statement i use this for high performance 

            preparedStatementPerson.execute();

        } catch (SQLException ex) {

            Logger.getLogger(EMPDao.class.getName()).log(Level.SEVERE, null, ex);
        }

        return true;
    }

Answer 1

根据SQLite Foreign Key Support和How do you enforce foreign key constraints in SQLite through Java? 的回答，它应该在执行任何查询之前配置数据库连接。我有这个问题，因为我没有强制执行外键约束。

public static final String DB_URL = "jdbc:sqlite:database.db";  
public static final String DRIVER = "org.sqlite.JDBC";  

public static Connection getConnection() throws ClassNotFoundException {  
    Class.forName(DRIVER);  
    Connection connection = null;  
    try {  
        SQLiteConfig config = new SQLiteConfig(); //I add this configuration 
        config.enforceForeignKeys(true);  
        connection = DriverManager.getConnection(DB_URL,config.toProperties());  
    } catch (SQLException ex) {}  
    return connection;  
}

如何从父表中删除行有子表的引用列？

1 个答案: