python中使用excutemany执行update语句，批量更新

# coding:utf8
import pymysql
import logging
 
connection = pymysql.connect(host=HOST, port=3306, user=USER, password=PASSWORD,                        
               db=DATABASE,charset='utf8mb4',cursorclass=pymysql.cursors.DictCursor)
cursor = connection.cursor()
flag_List = ["A", "B", "C", "D"]  # 存储flage的值
id_list = ["1", "2", "3", "4"]  # 存储id的值
commit_id_list = [(flag_List[i], id_list[i]) for i in range(len(id_list))]  
# commit_id_list必须是list[tuple(),tuple()...]或tuple(tuple(),tuple()...)的形式
 
with connection.cursor() as cursor:
    try:
        sql = "update mydatabase SET flag=(%s) where id=(%s)"
        cursor.executemany(sql, commit_id_list)  # commit_id_list上面已经说明
        connection.commit()
    except:
        logging.exception("exception")
        connection.rollback()
connection.close()