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java如何从父表中删除具有引用列的行到子表?

我在javaFx项目和SQlite数据库中使用JDBC。我有两个表"PROJECT""SMAllPROJECT",比如PROJECT有这个结构PROJECT(name,date,state)SMAllPROJECT有这个结构SMAllPROJECT(name,date,state,*project_name*)Project_name是从PROJECT tablename列引用的

我正在尝试从PROJECT中删除行,SMAllPoject中引用的行应该被删除。在sqlitestudio中,当我从父表中应用delete行时,我配置了onCascade方法,当我在sqlitestudio中测试它时,一切都很好,但在我的代码中,它只是从父表中删除了行

这是我的代码:

控制器方法

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();

        }

    }

DAO模式方法

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;
    }

这是我的DDL

CREATE TABLE PROJECT (
    NAME VARCHAR2 (100) PRIMARY KEY,
    STATE  VARCHAR2 (100),
    DATEDBT DATE,
 );

CREATE TABLE SMALLPROJECT (
    NAMEPROJECT       VARCHAR2 (100) REFERENCES PROJECT (NAME) ON DELETE CASCADE
                                                          ON UPDATE CASCADE,
    NAME VARCHAR2 (20)  PRIMARY KEY,
    DATEDBT     DATE,
    STATE VARCHAR2 (20)  PRIMARY KEY

    );

共 (1) 个答案

  1. # 1 楼答案

    根据SQLite Foreign Key SupportHow do you enforce foreign key constraints in SQLite through Java? 的答案 ,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;  
    }