如何使用与指定时间戳关联的值填充新列？

import mysql.connector
from datetime import datetime

# 连接到MySQL数据库
cnx = mysql.connector.connect(user='username', password='password',
                              host='localhost', database='database_name')

# 创建游标对象
cursor = cnx.cursor()

# 查询数据表并获取时间戳和相关值
query = "SELECT timestamp_column, value_column FROM table_name"
cursor.execute(query)

# 遍历查询结果并更新新列
for (timestamp, value) in cursor:
    # 处理时间戳
    timestamp = datetime.strptime(timestamp, "%Y-%m-%d %H:%M:%S")
    
    # 根据时间戳的值进行填充操作，这里仅作示例，可以根据具体需求进行修改
    if timestamp.hour < 12:
        new_value = "上午"
    else:
        new_value = "下午"
    
    # 更新新列的值
    update_query = "UPDATE table_name SET new_column = %s WHERE timestamp_column = %s"
    cursor.execute(update_query, (new_value, timestamp))

# 提交更改并关闭连接
cnx.commit()
cursor.close()
cnx.close()