Python3实现mysql连接和数据框的形成，具体代码如下所示：

# -*- coding:utf-8 -*-
# __author__ = "LQ"
import pymysql
import pandas as pd
import numpy as np
from sklearn import preprocessing
#返回数据库连接
def dbcconnect():
  conn = pymysql.connect(host='ip', port=3306, user='username', passwd='password',db='db')
  return conn
#接收sql返回查询结果
def selects(sql):
  conn=dbcconnect()
  cursor = conn.cursor()
  cursor.execute(sql)
  # 获取剩余结果所有数据
  results = cursor.fetchall()
  conn.commit()
  cursor.close()
  return results
#接收sql返回数据框
def selectDf(sql):
  conn=dbcconnect()
  cursor = conn.cursor()
  cursor.execute(sql)
  # 获取剩余结果所有数据
  results = cursor.fetchall()
  # 获取列名
  cols = [i[0] for i in cursor.description]
  # sql内表转换pandas的DF
  df = pd.DataFrame(np.array(results), columns=cols).astype(float)
  conn.commit()
  cursor.close()
  return df

总结