419

我想INSERT在 Java 中使用 JDBC 在数据库(在我的情况下是 Microsoft SQL Server)中记录。同时,我想获取插入ID。如何使用 JDBC API 实现这一点?

4

12 回答 12

715

如果它是自动生成的密钥,那么您可以使用Statement#getGeneratedKeys()它。您需要调用它与Statement用于INSERT. 您首先需要创建Statement.RETURN_GENERATED_KEYS用于通知 JDBC 驱动程序返回密钥的语句。

这是一个基本示例:

public void create(User user) throws SQLException {
    try (
        Connection connection = dataSource.getConnection();
        PreparedStatement statement = connection.prepareStatement(SQL_INSERT,
                                      Statement.RETURN_GENERATED_KEYS);
    ) {
        statement.setString(1, user.getName());
        statement.setString(2, user.getPassword());
        statement.setString(3, user.getEmail());
        // ...

        int affectedRows = statement.executeUpdate();

        if (affectedRows == 0) {
            throw new SQLException("Creating user failed, no rows affected.");
        }

        try (ResultSet generatedKeys = statement.getGeneratedKeys()) {
            if (generatedKeys.next()) {
                user.setId(generatedKeys.getLong(1));
            }
            else {
                throw new SQLException("Creating user failed, no ID obtained.");
            }
        }
    }
}

请注意,您依赖于 JDBC 驱动程序是否有效。目前,大多数最新版本都可以工作,但如果我是正确的,Oracle JDBC 驱动程序仍然有点麻烦。MySQL 和 DB2 已经支持它很久了。PostgreSQL 不久前开始支持它。我无法评论 MSSQL,因为我从未使用过它。

对于 Oracle,您可以在同一事务中直接调用CallableStatement带有RETURNING子句或 a SELECT CURRVAL(sequencename)(或任何特定于 DB 的语法)的a,以获取最后生成的密钥。INSERT另请参阅此答案

于 2009-12-16T15:03:14.127 回答
27
  1. 创建生成的列

    String generatedColumns[] = { "ID" };
    
  2. 将此生成的列传递给您的语句

    PreparedStatement stmtInsert = conn.prepareStatement(insertSQL, generatedColumns);
    
  3. 使用ResultSet对象获取语句上的 GeneratedKeys

    ResultSet rs = stmtInsert.getGeneratedKeys();
    
    if (rs.next()) {
        long id = rs.getLong(1);
        System.out.println("Inserted ID -" + id); // display inserted record
    }
    
于 2016-12-06T04:59:53.567 回答
9

我正在从基于 JDBC 的单线程应用程序中访问 Microsoft SQL Server 2008 R2,并在不使用 RETURN_GENERATED_KEYS 属性或任何 PreparedStatement 的情况下拉回最后一个 ID。看起来像这样:

private int insertQueryReturnInt(String SQLQy) {
    ResultSet generatedKeys = null;
    int generatedKey = -1;

    try {
        Statement statement = conn.createStatement();
        statement.execute(SQLQy);
    } catch (Exception e) {
        errorDescription = "Failed to insert SQL query: " + SQLQy + "( " + e.toString() + ")";
        return -1;
    }

    try {
        generatedKey = Integer.parseInt(readOneValue("SELECT @@IDENTITY"));
    } catch (Exception e) {
        errorDescription = "Failed to get ID of just-inserted SQL query: " + SQLQy + "( " + e.toString() + ")";
        return -1;
    }

    return generatedKey;
} 

这篇博文很好地隔离了三个主要的 SQL Server“最后一个 ID”选项: http: //msjawahar.wordpress.com/2008/01/25/how-to-find-the-last-identity-value-inserted-in-the -sql-server/ - 还不需要另外两个。

于 2011-06-24T05:52:21.257 回答
8

使用时遇到“不支持的功能”错误Statement.RETURN_GENERATED_KEYS,请尝试以下操作:

String[] returnId = { "BATCHID" };
String sql = "INSERT INTO BATCH (BATCHNAME) VALUES ('aaaaaaa')";
PreparedStatement statement = connection.prepareStatement(sql, returnId);
int affectedRows = statement.executeUpdate();

if (affectedRows == 0) {
    throw new SQLException("Creating user failed, no rows affected.");
}

try (ResultSet rs = statement.getGeneratedKeys()) {
    if (rs.next()) {
        System.out.println(rs.getInt(1));
    }
    rs.close();
}

BATCHID自动生成的 id在哪里。

于 2015-12-14T08:39:14.767 回答
6

我只想回答帖子,而不是评论。


接口java.sql.PreparedStatement

  1. columnIndexes « 您可以使用接受 columnIndexes 和 SQL 语句的 prepareStatement 函数。 其中 columnIndexes 允许的常量标志是 Statement.RETURN_GENERATED_KEYS 1或 Statement.NO_GENERATED_KEYS[2],可能包含一个或多个“?”的 SQL 语句 IN 参数占位符。

    句法 ”

    Connection.prepareStatement(String sql, int autoGeneratedKeys)
    Connection.prepareStatement(String sql, int[] columnIndexes)
    

    例子:

    PreparedStatement pstmt = 
        conn.prepareStatement( insertSQL, Statement.RETURN_GENERATED_KEYS );
    

  1. columnNames «列出 columnNames 之类的'id', 'uniqueID', ...。在包含应返回的自动生成键的目标表中。如果 SQL 语句不是INSERT语句,驱动程序将忽略它们。

    句法 ”

    Connection.prepareStatement(String sql, String[] columnNames)
    

    例子:

    String columnNames[] = new String[] { "id" };
    PreparedStatement pstmt = conn.prepareStatement( insertSQL, columnNames );
    

完整示例:

public static void insertAutoIncrement_SQL(String UserName, String Language, String Message) {
    String DB_URL = "jdbc:mysql://localhost:3306/test", DB_User = "root", DB_Password = "";

    String insertSQL = "INSERT INTO `unicodeinfo`( `UserName`, `Language`, `Message`) VALUES (?,?,?)";
            //"INSERT INTO `unicodeinfo`(`id`, `UserName`, `Language`, `Message`) VALUES (?,?,?,?)";
    int primkey = 0 ;
    try {
        Class.forName("com.mysql.jdbc.Driver").newInstance();
        Connection conn = DriverManager.getConnection(DB_URL, DB_User, DB_Password);

        String columnNames[] = new String[] { "id" };

        PreparedStatement pstmt = conn.prepareStatement( insertSQL, columnNames );
        pstmt.setString(1, UserName );
        pstmt.setString(2, Language );
        pstmt.setString(3, Message );

        if (pstmt.executeUpdate() > 0) {
            // Retrieves any auto-generated keys created as a result of executing this Statement object
            java.sql.ResultSet generatedKeys = pstmt.getGeneratedKeys();
            if ( generatedKeys.next() ) {
                primkey = generatedKeys.getInt(1);
            }
        }
        System.out.println("Record updated with id = "+primkey);
    } catch (InstantiationException | IllegalAccessException | ClassNotFoundException | SQLException e) {
        e.printStackTrace();
    }
}
于 2018-01-18T13:20:04.580 回答
3

我正在使用SQLServer 2008,但我有一个开发限制:我不能使用新的驱动程序,我必须使用“com.microsoft.jdbc.sqlserver.SQLServerDriver”(我不能使用“com.microsoft.sqlserver.jdbc .SQLServerDriver”)。

这就是解决方案为我conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS)抛出java.lang.AbstractMethodError的原因。在这种情况下,我找到的一个可能的解决方案是 Microsoft 建议的旧解决方案: 如何使用 JDBC 检索 @@IDENTITY 值

import java.sql.*; 
import java.io.*; 

public class IdentitySample
{
    public static void main(String args[])
    {
        try
        {
            String URL = "jdbc:microsoft:sqlserver://yourServer:1433;databasename=pubs";
            String userName = "yourUser";
            String password = "yourPassword";

            System.out.println( "Trying to connect to: " + URL); 

            //Register JDBC Driver
            Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();

            //Connect to SQL Server
            Connection con = null;
            con = DriverManager.getConnection(URL,userName,password);
            System.out.println("Successfully connected to server"); 

            //Create statement and Execute using either a stored procecure or batch statement
            CallableStatement callstmt = null;

            callstmt = con.prepareCall("INSERT INTO myIdentTable (col2) VALUES (?);SELECT @@IDENTITY");
            callstmt.setString(1, "testInputBatch");
            System.out.println("Batch statement successfully executed"); 
            callstmt.execute();

            int iUpdCount = callstmt.getUpdateCount();
            boolean bMoreResults = true;
            ResultSet rs = null;
            int myIdentVal = -1; //to store the @@IDENTITY

            //While there are still more results or update counts
            //available, continue processing resultsets
            while (bMoreResults || iUpdCount!=-1)
            {           
                //NOTE: in order for output parameters to be available,
                //all resultsets must be processed

                rs = callstmt.getResultSet();                   

                //if rs is not null, we know we can get the results from the SELECT @@IDENTITY
                if (rs != null)
                {
                    rs.next();
                    myIdentVal = rs.getInt(1);
                }                   

                //Do something with the results here (not shown)

                //get the next resultset, if there is one
                //this call also implicitly closes the previously obtained ResultSet
                bMoreResults = callstmt.getMoreResults();
                iUpdCount = callstmt.getUpdateCount();
            }

            System.out.println( "@@IDENTITY is: " + myIdentVal);        

            //Close statement and connection 
            callstmt.close();
            con.close();
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
        }

        try
        {
            System.out.println("Press any key to quit...");
            System.in.read();
        }
        catch (Exception e)
        {
        }
    }
}

这个解决方案对我有用!

我希望这有帮助!

于 2013-09-10T09:41:04.470 回答
2

您可以使用以下 java 代码来获取新插入的 id。

ps = con.prepareStatement(query, Statement.RETURN_GENERATED_KEYS);
ps.setInt(1, quizid);
ps.setInt(2, userid);
ps.executeUpdate();

ResultSet rs = ps.getGeneratedKeys();
if (rs.next()) {
    lastInsertId = rs.getInt(1);
}
于 2019-05-21T10:35:58.147 回答
1

也可以将它与 normal 一起使用Statement(不仅仅是PreparedStatement

Statement statement = conn.createStatement();
int updateCount = statement.executeUpdate("insert into x...)", Statement.RETURN_GENERATED_KEYS);
try (ResultSet generatedKeys = statement.getGeneratedKeys()) {
  if (generatedKeys.next()) {
    return generatedKeys.getLong(1);
  }
  else {
    throw new SQLException("Creating failed, no ID obtained.");
  }
}
于 2018-05-04T19:33:08.160 回答
0

使用 Hibernate 的 NativeQuery,需要返回 ResultList 而不是 SingleResult,因为 Hibernate 修改了原生查询

INSERT INTO bla (a,b) VALUES (2,3) RETURNING id

INSERT INTO bla (a,b) VALUES (2,3) RETURNING id LIMIT 1

如果您尝试获得单个结果,这会导致大多数数据库(至少是 PostgreSQL)抛出语法错误。之后,您可以从列表中获取结果 id(通常只包含一项)。

于 2018-04-23T08:01:14.107 回答
0

就我而言->

ConnectionClass objConnectionClass=new ConnectionClass();
con=objConnectionClass.getDataBaseConnection();
pstmtGetAdd=con.prepareStatement(SQL_INSERT_ADDRESS_QUERY,Statement.RETURN_GENERATED_KEYS);
pstmtGetAdd.setString(1, objRegisterVO.getAddress());
pstmtGetAdd.setInt(2, Integer.parseInt(objRegisterVO.getCityId()));
int addId=pstmtGetAdd.executeUpdate();              
if(addId>0)
{
    ResultSet rsVal=pstmtGetAdd.getGeneratedKeys();
    rsVal.next();
    addId=rsVal.getInt(1);
}
于 2018-08-29T12:10:09.637 回答
0

如果您使用的是 Spring JDBC,则可以使用 Spring 的 GeneratedKeyHolder 类来获取插入的 ID。

查看此答案... 如何使用 Spring Jdbctemplate.update(String sql, obj...args) 获取插入的 id

于 2019-01-25T02:45:43.713 回答
-6
Connection cn = DriverManager.getConnection("Host","user","pass");
Statement st = cn.createStatement("Ur Requet Sql");
int ret  = st.execute();
于 2017-03-14T22:35:42.163 回答