获得自动增长的MySQL主键
下面的脚本教您如何获得自动增长的MySQL主键,如果您对MySQL主键方面感兴趣的话,不妨一看,相信对您学习MySQL主键方面会有所启迪。
import java.sql.Connection; import java.sql.ResultSet; import java.sql.Statement; public class GetKey { ResultSet rs = null; Connection conn = null; Statement stmt = null; // 加入同一个连接发生其他查询,Key会被重写所以不准确 public void getId() { try { Statement stmt = conn.createStatement(); stmt.executeUpdate("insert into tb (name) values ('Key')"); rs = stmt.executeQuery("SELECT LAST_INSERT_ID()"); int autoIncKeyFromFunc = -1; if (rs.next()) { autoIncKeyFromFunc = rs.getInt(1); System.out.println("autoIncKeyFromFunc: " + autoIncKeyFromFunc); } } catch (Exception e) { System.out.print("有异常发生!"); } } // getGeneratedKeys()是每次创建一个Statement 实例,所以是安全的! public void getId_() { try { stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_UPDATABLE); stmt.executeUpdate("insert into tb (name) values ('x')"); int autoIncKeyFromApi = -1; rs = stmt.getGeneratedKeys(); if (rs.next()) { autoIncKeyFromApi = rs.getInt(1); System.out.println("Key returned from getGeneratedKeys():" + autoIncKeyFromApi); } } catch (Exception e) { System.out.print("有异常发生!"); } } public static void main(String[] args) { GetKey get = new GetKey(); get.getId(); get.getId_(); } }