如何从父项 table 中删除行具有子项 table 的引用列?

How can I delete row from parent table has a referenced column to child table?

我在带有 SQlite 数据库的 javaFx 项目中使用 JDBC。我有两个 tables "PROJECT""SMAllPROJECT" 例如 PROJECT 有这个结构 PROJECT(name,date,state)SMAllPROJECT 有这个结构 SMAllPROJECT(name,date,state,*project_name*)Project_name 引用自 PROJECT tablename 列。

我正在尝试从 PROJECT 中删除行,并且应该删除 SMAllPoject 中引用的行。在 sqlite studio 中,我配置了 onCascade 方法,当我应用从父 table 中删除一行时,当我在 SQlite studio 中测试它时,一切都很好,但在我的代码中,它只从父 [=43] 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

    );

根据SQLite Foreign Key Support的回答,你如何通过Java在SQLite中执行外键约束? ,它应该在执行任何之前配置数据库连接 query.I 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;  
}