java - SQL JAVA JDBC deleteForCustomerID

Question

此方法本质上应该删除 creditcard 类中的客户(它在删除时设置为级联) DB)但我认为这是不正确的。

我的sql语句是:

final static String deleteSQL = "DELETE FROM creditcard WHERE customer_id = ?;"; 

任何建议将不胜感激。我只是不明白我的做法错在哪里。

public void deleteForCustomerID(Connection connection, Long customerID) throws SQLException, DAOException 
{
    if (customerID == null) 
    {
        throw new DAOException("Trying to delete customer with NULL ID");
    }

    PreparedStatement ps = null;
    try 
    {
        ps = connection.prepareStatement(deleteSQL);
        ps.setLong(1, customerID);
        int rows = ps.executeUpdate();

    }
    finally {}

}

JUnit 测试的代码是:

@Test
public void testDeleteForCustomerID() throws Exception
{
    DataSource ds = DataSourceManager.getDataSource();
    Connection connection = ds.getConnection();
    // Do not commit changes made by this test.
    connection.setAutoCommit(false);

    CreditCardDAO dao = new CreditCardDaoImpl();

    CreditCard ccard = dao.retrieveForCustomerID(connection, customerID);
    assertNotNull(ccard);
    dao.deleteForCustomerID(connection, customerID);
    CreditCard ccard2 = dao.retrieveForCustomerID(connection, customerID);
    assertNull(ccard2);

    // Do not commit changes made by this test.
    connection.rollback();
    connection.setAutoCommit(true);
    connection.close();
}

我收到以下错误:

java.lang.AssertionError: expected null, but was: at org.junit.Assert.fail(Assert.java:88) at org.junit.Assert.failNotNull(Assert.java:755) at org.junit.Assert.assertNull(Assert.java:737) at org.junit.Assert.assertNull(Assert.java:747)

Answer 1

我认为您的deletesql字符串应该按如下方式更正。引号内不需要分号

   final static String deleteSQL = "DELETE FROM creditcard WHERE customer_id = ?";