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_();
    }
}