使用 PreparedStatement.RETURN_GENERATED_KEYS 获取刚刚插入语句的ID值

使用 PreparedStatement.RETURN_GENERATED_KEYS  可以获取刚刚插入自增ID值

下面这段代码摘自 hibernate3(版本为 hibernate-distribution-3.3.1.GA)的 AbstractBatcher (在 org.hibernate.jdbc 包中)类中

private PreparedStatement getPreparedStatement(
			final Connection conn,
	        String sql,
	        boolean scrollable,
	        final boolean useGetGeneratedKeys,
	        final String[] namedGeneratedKeys,
	        final ScrollMode scrollMode,
	        final boolean callable) throws SQLException {
                             
                   //省略...   
			
		  //useGetGeneratedKeys 表示是否是自增字段
		else if ( useGetGeneratedKeys ) { 
			result = conn.prepareStatement( sql, PreparedStatement.RETURN_GENERATED_KEYS );
		}
		
                 //省略...  

		return result;

}

 

the jdbc example:

package com.laoyangx.jdbc.chapter0;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;


public class TestPreparedStatement {

	/**
	 * @param args
	 * 使用PreparedStatement.RETURN_GENERATED_KEYS 获取刚刚插入语句的ID值
	 */
	public static void main(String[] args)  {
		
		System.err.println("Adding new column in table example!");
		Connection conn=null;
		PreparedStatement ps=null;
		String sql="insert into customer(customer_name) values(?)";
		ResultSet rs=null;
		
		try {
			Class.forName("com.mysql.jdbc.Driver");
			conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/hibernate","root","123456");
			
			ps = conn.prepareStatement( sql, PreparedStatement.RETURN_GENERATED_KEYS );
			ps.setString(1, "jdbc1");
			ps.executeUpdate();
			rs=ps.getGeneratedKeys();
			
			if ( !rs.next() ) {
			   System.err.println("wrong ...");
			}
			final int CUSTOMER_ID_COLUMN_INDEX=1;
			System.err.println(rs.getInt( CUSTOMER_ID_COLUMN_INDEX )); //输出刚插入数据返回的Id号
			
		} catch (ClassNotFoundException e) {
			
			e.printStackTrace();
		} catch (SQLException e) {
			
			e.printStackTrace();
		}
		finally{
			
				try {
					if(rs!=null) rs.close();
					if(ps!=null) ps.close();
					if(conn!=null) conn.close();
				} catch (SQLException e) {
					
					e.printStackTrace();
				}
			
		}
		
	}

}

运行程序之前，customer表中的数据如下图所示:

运行程序之后，customer表中的数据如下图所示:

控制台的输出如下图所示：