玩删除时的框架引用完整性约束

Question

我创建了一些Model对象来表示一个有几个客户的公司，以及一个由公司和客户组合以及几个发票行组成的发票对象。我已经创建了以下模型对象：

@Entity
public class Company extends Model {
    @OneToMany(mappedBy="company")
    public Set<Client> clients;
}
@Entity
public class Client extends Model {
    @ManyToOne
    public Company company;
}
@Entity
public class Invoice extends Model {
    @ManyToOne
    public Company company;
    @ManyToOne
    public Client client;
    @OneToMany(mappedBy="invoice", cascade=CascadeType.ALL)
    public Set<InvoiceLine> invoiceLines;
}
@Entity
public class InvoiceLine extends Model {
    @ManyToOne
    public Invoice invoice;
}

测试：

@Test
public void testModels() {
    Client client = createClient();
    Company company = createCompany();
    company.clients = new HashSet<Client>();
    company.clients.add(client);
    company.save();
    Invoice invoice = createInvoice(client, company);
    InvoiceLine invoiceLine1 = createInvoiceLine(invoice);
    InvoiceLine invoiceLine2 = createInvoiceLine(invoice);
    Set<InvoiceLine> invoiceLines = new HashSet<InvoiceLine>();
    invoiceLines.add(invoiceLine1);
    invoiceLines.add(invoiceLine2);
    invoice.invoiceLines = invoiceLines;
    invoice.save();
    Company retrievedCompany = Company.find("byName", company.name).first();
    assertNotNull(retrievedCompany);
    assertEquals(1, retrievedCompany.clients.size());
    assertEquals(2, InvoiceLine.count());
    assertEquals(1, Invoice.deleteAll());
    assertNull(Invoice.all());
    assertNull(InvoiceLine.all());

}

当运行一个测试，创建一个有两个发票行的发票，并试图删除这个发票时，我得到了以下错误：

org.h2.jdbc.JdbcSQLException：引用完整性约束冲突："FK3004B0A1F4110EF6:PUBLIC.INVOICELINE外键（INVOICE_ID）REFERENCES>PUBLIC.voice（ID）"；SQL语句：从发票中删除〔23003-149〕

我做错了什么？

Answer 1

您在invoice.delete()中尝试过吗？问题是deleteAll()没有级联删除操作。

deleteAll()在内部使用javax.persistence.Query，而delete()使用EntityManager的remove()方法。JPA中的级联由JPA处理，而不是由数据库处理，并且JPA不会像deleteAll()执行的那样级联大容量删除
有关批量删除/更新的更多信息，请查看此链接。

此外：如果您已经在createInvoiceLine()中将Invoice设置为父级，则向Invoice添加InvoiceLine实体是多余的。只需在执行断言之前执行invoice.refresh()即可。

也许下面的单元测试可以解决问题。Parent1就像你的Invoice。而Child1就像你的InvoiceLine。

import java.util.*;
import javax.persistence.*;
import org.junit.*;
import play.test.*;
import models.*;
public class Parent1Test extends UnitTest {
    public Parent1 p;
    public Child1 c1;
    public Child1 c2;
    public Child1 c3;
    @Before
    public void setUp() {
        Fixtures.deleteAllModels();
        p = new Parent1();
        c1 = new Child1();
        c2 = new Child1();
        c3 = new Child1();
    }
    public void byAddingParentToChilds() {
        c1.parent = p;
        c2.parent = p;
        c3.parent = p;
        c1.save();
        c2.save();
        c3.save();
        p.refresh();
    }
    @Test
    public void testByAddingParentToChilds() {
        byAddingParentToChilds();
        assertEquals(p.id, c1.parent.id);
        assertEquals(3, Child1.count());
    }
    public void byAddingChildsToParent() {
        p.childs = new ArrayList<Child1>();
        p.childs.add(c1);
        p.childs.add(c2);
        p.childs.add(c3);
        p.save();
    }
    @Test
    public void testByAddingChildsToParent() {
        // By adding childs
        byAddingChildsToParent();
        c1.refresh();
        assertEquals(3, Child1.count());
        // This will be null, because you added the childs to the 
        // parent while the childs are the owning side of the 
        // relation.
        assertNull(c1.parent);
    }
    @Test
    public void testDeletingAfterAddingParentToChilds() {
        byAddingParentToChilds();
        p.delete();
        assertEquals(0, Parent1.count());
        assertEquals(0, Child1.count());
    }
    @Test
    public void testDeletingAfterAddingChildsToParent() {
        byAddingChildsToParent();
        p.delete();
        assertEquals(0, Parent1.count());
        assertEquals(0, Child1.count());
    }
    @Test(expected=PersistenceException.class)
    public void testDeleteAllAfterAddingParentToChilds() {
        byAddingParentToChilds();
        // The cascading doesn't work for deleteAll() so this line
        // will throw an exception because the child elements still
        // reference the parent.
        assertEquals(1, Parent1.deleteAll());
    }
    @Test
    public void testDeleteAllAfterAddingChildsToParent() {
        byAddingChildsToParent();
        assertEquals(1, Parent1.deleteAll());
        assertEquals(0, Parent1.count());
        // Again the cascading doesn't work for deleteAll()
        assertEquals(3, Child1.count());
    }
}

Answer 2

您正在尝试删除所有发票，但仍有一些InvoiceLine链接到它。

请尝试先删除发票行，然后再删除发票。