MYSQL大表加索引的实现

CREATE TABLE `test_page1`  (
  `id` int(11)  NULL,
  `username` int(252) not  NULL,
  `password` int(252)  NULL,
  `create_time` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci not NULL ,
  `update_time` datetime(0) NULL DEFAULT NULL,
  PRIMARY KEY (`create_time`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1000001 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

public class Connect {
    //    导入驱动jar包或添加Maven依赖（这里使用的是Maven，Maven依赖代码附在文末）
    static {
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }
    //  获取数据库连接对象
    public static Connection getConn() {
        Connection conn = null;
        try {
            //  rewriteBATchedStatements=true,一次插入多条数据，只插入一次
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/xxx?rewriteBatchedStatements=true", "root", "xxx");
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        return conn;
    }
    //  释放资源
    public static void closeAll(AutoCloseable... autoCloseables) {
        for (AutoCloseable autoCloseable : autoCloseables) {
            if (autoCloseable != null) {
                try {
                    autoCloseable.close();
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    }
}

public class InsertData {
    private static ThreadPoolExecutor getDefaultThreadPool() {
        ThreadPoolExecutor result = new ThreadPoolExecutor(0, 1000, 1, TimeUnit.SECONDS, new SynchronousQueue<>());
        result.setThreadFactory(new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                return new Thread(r, "deterministic runner thread");
            }
        });
        return result;
    }
    
    public static void main(String[] args) {
            for (int j = 0; j < 100; j++) {
                long start = System.currentTimeMillis();    //  获取系统当前时间，方法开始执行前记录
                Connection conn = Connect.getConn();        //  调用刚刚写好的用于获取连接数据库对象的静态工具类
                String sql = "insert into test_page1 values(null,?,?,?,NOW())";  //  要执行的sql语句
                PreparedStatement ps = null;
                getDefaultThreadPool().execute(() -> {
                    try {
                    PreparedStatement finalPs = conn.prepareStatement(sql);
                        //  不断产生sql
                        for (int i = 0; i < 20000; i++) {
                            finalPs.setString(1, Math.ceil(Math.random() * 1000000) + "");
                            finalPs.setString(2, Math.ceil(Math.random() * 1000000) + "");
                            finalPs.setString(3, UUID.randomUUID().toString());  //  UUID该类用于随机生成一串不会重复的字符串
                            finalPs.addBatch();  //  将一组参数添加到此 PreparedStatement 对象的批处理命令中。
                        }
                        int[] ints = new int[0];//   将一批命令提交给数据库来执行，如果全部命令执行成功，则返回更新计数组成的数组。
                        ints = finalPs.executeBatch();
                        //  如果数组长度不为0，则说明sql语句成功执行，即数据添加成功！
                        if (ints.length > 0) {
                            System.out.println("数据添加成功！！");
                        }
                    } catch (SQLException e) {
                        throw new RuntimeException(e);
                    }finally {
                        Connect.closeAll(conn, ps);  //  调用刚刚写好的静态工具类释放资源
                    }
                  });
                long end = System.currentTimeMillis();  //  再次获取系统时间
                System.out.println("所用时长:" + (end - start) / 1000 + "秒");  //  两个时间相减即为方法执行所用时长
            }
    }
}

alter table test_page1 add index create_time_index(create_time)

BEGIN;
select * from test_page1 where username = 852;

alter table test_page1 add index create_time_index(create_time)

insert into test_page1(id,username,password,create_time,update_time) values(null,1,2,'6144423733',NOW());