python 实现数据库中数据添加、查询与更新的示例代码

import pymysql
import random
import time
from get_userinfo import get_userinfo
from get_info import get_info
from get_tags import get_tags
from get_tuser_id import get_utag


class DatabaseAccess():
  def __init__(self):
    self.__db_host = "xxxxx"
    self.__db_port = 3307
    self.__db_user = "root"
    self.__db_password = "123456"
    self.__db_database = "xxxxxx"
  # 连接数据库
  def isConnectionOpen(self):
    self.__db = pymysql.connect(
      host=self.__db_host,
      port=self.__db_port,
      user=self.__db_user,
      password=self.__db_password,
      database=self.__db_database,
      charset='utf8'
    )
  
  # 插入数据
  def linesinsert(self,n,user_id,tags_id,created_at):
 
    self.isConnectionOpen()
    # 创建游标
    global cursor
    conn = self.__db.cursor()
    try:
      sql1 = '''
      INSERT INTO `codeforge_new`.`cf_user_tag`(`id`, `user_id`, 
      `tag_id`, `created_at`, `updated_at`) VALUES ({}, {}, 
      {}, '{}', '{}');
      '''.format(n,user_id,tags_id,created_at,created_at)
      
      # 执行SQL  
      conn.execute(sql1,)
    except Exception as e:
      print(e)
    finally:
      # 关闭游标
      conn.close()
      self.__db.commit()
      
      self.__db.close()
  
  def get_data(self):
    
    # 生成对应数据 1000条
    for i in range(0,1001):
      created_at = time.strftime('%Y-%m-%d %H:%M:%S',time.localtime())
      # print(create_at)
      # 用户id
      tuserids = []
      tuserid_list = get_utag()
      for tuserid in tuserid_list:
        tuserids.append(tuserid[0])
      # print(tuserids)
      userid_list = get_userinfo()
      user_id = random.choice(userid_list)[0]
      if user_id not in tuserids:
        user_id=user_id
      
        # 标签id
        tagsid_list = get_tags()
        tags_id = random.choice(tagsid_list)[0]
        self.linesinsert(i,user_id,tags_id,created_at)


if __name__ == "__main__":
  # 实例化对象
  db=DatabaseAccess()
  db.get_data()

import pymysql
import pandas as pd
import numpy as np


def get_tags():
  # 连接数据库，地址，端口，用户名，密码，数据库名称，数据格式
  conn = pymysql.connect(host='xxx.xxx.xxx.xxx',port=3307,user='root',passwd='123456',db='xxxx',charset='utf8')
  cur = conn.cursor()
  # 表cf_users中获取所有用户id
  sql = 'select id from cf_tags where id between 204 and 298'
  # 将user_id列转成列表输出
  df = pd.read_sql(sql,con=conn)
  # 先使用array()将DataFrame转换一下
  df1 = np.array(df)
  # 再将转换后的数据用tolist()转成列表
  df2 = df1.tolist()
  # cur.execute(sql)
  # data = cur.fetchone()
  # print(df)
  # print(df1)
  # print(df2)
  return df2
  conn.close()

import pymysql
import pandas as pd
import numpy as np


def get_tags():
  # 连接数据库，地址，端口，用户名，密码，数据库名称，数据格式
  conn = pymysql.connect(host='xxx.xxx.xxx.xxx',port=3307,user='root',passwd='123456',db='xxxx',charset='utf8')
  cur = conn.cursor()
  # 表cf_users中获取所有用户id
  sql = 'select id from cf_tags where id between 204 and 298'
  # 将user_id列转成列表输出
  df = pd.read_sql(sql,con=conn)
  # 先使用array()将DataFrame转换一下
  df1 = np.array(df)
  # 再将转换后的数据用tolist()转成列表
  df2 = df1.tolist()
  # cur.execute(sql)
  # data = cur.fetchone()
  # print(df)
  # print(df1)
  # print(df2)
  return df2
  conn.close()