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"
和 "SMAllPROJECT"
例如 PROJECT 有这个结构 PROJECT(name,date,state)
和 SMAllPROJECT
有这个结构 SMAllPROJECT(name,date,state,*project_name*)
。 Project_name
引用自 PROJECT table
的 name
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和的回答,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;
}
我在带有 SQlite 数据库的 javaFx 项目中使用 JDBC。我有两个 tables "PROJECT"
和 "SMAllPROJECT"
例如 PROJECT 有这个结构 PROJECT(name,date,state)
和 SMAllPROJECT
有这个结构 SMAllPROJECT(name,date,state,*project_name*)
。 Project_name
引用自 PROJECT table
的 name
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和的回答,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;
}