Question

Scenerio：

我将CSV文件插入我的数据库。
我使用jdbc驱动程序迭代文件并执行我的插入
name列unique，因此当相同值到达时，插入不会更改表格
我使用INSERT INTO IGNORE来防止迭代在事件发生时中断
我使用LAST_INSERT_ID（）在插入的下一个表中添加为FK
INSERT_IGNORE发生时我得到0

如何解决此问题？

 Connection con = null;

    try
    {
      Class.forName("com.mysql.jdbc.Driver");
      con = DriverManager.getConnection(URL, USERNAME, PASSWORD);
      con.setAutoCommit(false);

      Statement s1 = (Statement) con.createStatement();
      s1.executeUpdate("INSERT IGNORE INTO ORIGIN (ORI_NAME) VALUES(\""
          + d.getOriginName() + "\")");

      Statement s2 = (Statement) con.createStatement();
      s2.executeUpdate("INSERT IGNORE INTO STOCK (ORI_ID,S_TITLE) VALUES ("
          + "(SELECT ORI_ID FROM ORIGIN WHERE ORI_ID =LAST_INSERT_ID()),\""
          + d.getStockTitle() + "\")");

     }

      con.commit();

    }
    catch (Exception e)
    {
      if (con != null)
        try
        {
          con.rollback();
        }
        catch (SQLException e1)
        {
          e1.printStackTrace();
        }

      e.printStackTrace();
    }
    finally
    {
      if (con != null)
        try
        {
          con.close();
        }
        catch (SQLException e)
        {
          e.printStackTrace();
        }
    }

要插入数据库的CSV文件示例

US, P1, M, 200, 344
US, P1, L, 233, 344
US, P2, M, 444, 556
MX, Q4, L, 656, 777

表：http://sqlfiddle.com/#!2/b5752

Answer 1

您熟悉MySQL的ON DUPLICATE KEY UPDATE语法吗？

http://dev.mysql.com/doc/refman/5.0/en/insert-on-duplicate.html

 // Results are the same as doing an update.
 // Note the way the PK can be used to avoid an IGNORE.
 s1.executeUpdate("INSERT INTO ORIGIN (ORI_NAME) VALUES(\""
          + d.getOriginName() + "\" ON DUPLICATE KEY UPDATE ORI_ID=ORI_ID)");

此处涉及维护网站的失败电子邮件地址的实际示例：

http://blog.developpez.com/james-poulson/p10016/sql/ne-rien-modifier-en-cas-de-duplicate-key/

至于检索最后插入的id，以下内容来自上面的mysql.com链接：

Suppose that id is the AUTO_INCREMENT column. To make LAST_INSERT_ID() meaningful for updates, insert rows as follows:

INSERT INTO table (a,b,c) VALUES (1,2,3)
  ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id), c=3;

Answer 2

如果要获取后续插入的ID，则代码必须测试LAST_INSERT_ID的0值，如果得到它，请在表上执行SELECT以找到插入的FK的正确值。

在伪代码中，这看起来像：

$err = mysql("insert ignore into mytable values ($x, $y)")
if($err){
    do something for an error
}
$id = mysql("select last_insert_id()");
if($id == 0){
    $id = mysql("select id from othertable where condition is true for the record I want to reference in my insert");
    if($id == 0){
        do something for error
    }
}
mysql("insert into othertable VALUES ($id, other stuff)")

您必须将其翻译成您自己的应用程序和语言。

MySQL如何在使用INSERT IGNORE INTO时检索LAST_INSERT_ID的ID？

2 个答案: