SQL 错误：违反完整性约束：外键没有父级

Question

我正在努力找出我的查询做错了什么。 我没有创建数据库，但结构如下：

3 个表格：

车辆：品牌、电机、价格、名称、ID

选项：id、描述、价格

vehicule_option : id_vehicule, id_option

我猜 vehicule_option 有 2 个外键，但我找不到我添加的问题。 这是我的代码，第一部分工作正常：

public boolean create(Vehicule v){
        String query = "INSERT INTO vehicule (MARQUE, MOTEUR, PRIX, NOM) VALUES (";
        query += v.getMarque().getId() + ", "
                + v.getMoteur().getId() + ", "
                + v.getPrix() + ", \'"
                + v.getNom() + "\');";

        for (Option o : v.getOptions()){
            query += "INSERT INTO vehicule_option (id_vehicule, id_option) VALUES ("
                    + v.getId() + ", " + o.getId() + ");";
        }


        try{
            Statement state = this.connect.createStatement();
            ResultSet rs = state.executeQuery(query);
        } catch (SQLException e){
            e.printStackTrace();
        }
        return true;
    }

所以，我在这里所做的基本上是将两个值插入到正确的列中。 它给了我以下例外：

java.sql.SQLIntegrityConstraintViolationException: integrity constraint violation: foreign key no parent; SYS_FK_10132 table: VEHICULE_OPTION
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCStatement.fetchResult(Unknown Source)
    at org.hsqldb.jdbc.JDBCStatement.executeQuery(Unknown Source)
    at fr.ocr.sql.DAOVehicule.create(DAOVehicule.java:35)
    at fr.ocr.ihm.AddCarDialogBox$1.actionPerformed(AddCarDialogBox.java:151)
    at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
    at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
    at java.awt.Component.processMouseEvent(Unknown Source)
    at javax.swing.JComponent.processMouseEvent(Unknown Source)
    at java.awt.Component.processEvent(Unknown Source)
    at java.awt.Container.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Window.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: org.hsqldb.HsqlException: integrity constraint violation: foreign key no parent; SYS_FK_10132 table: VEHICULE_OPTION
    at org.hsqldb.error.Error.error(Unknown Source)
    at org.hsqldb.Constraint.getException(Unknown Source)
    at org.hsqldb.Constraint.checkInsert(Unknown Source)
    at org.hsqldb.StatementDML.performIntegrityChecks(Unknown Source)
    at org.hsqldb.StatementDML.insertSingleRow(Unknown Source)
    at org.hsqldb.StatementInsert.getResult(Unknown Source)
    at org.hsqldb.StatementDMQL.execute(Unknown Source)
    at org.hsqldb.Session.executeCompiledStatement(Unknown Source)
    at org.hsqldb.Session.executeDirectStatement(Unknown Source)
    at org.hsqldb.Session.execute(Unknown Source)
    ... 40 more

Answer 1

从您在此处显示的内容来看，车辆选项似乎有两个外键，即来自车辆表的 id 和来自选项表的 id。

当您插入时，车辆表中不存在车辆 ID，或者选项表中不存在选项 ID。

Answer 2

您刚刚插入了一条新的vehicule 记录，那么您如何知道v.getId() 中该记录的ID？

你没有，v.getId() 很可能是0，因为你正在创建一个新的。

Answer 3

如果您通过“o”变量进行迭代，您应该使用 o.getId() 而不是 v.getId()