python 3.6 +pyMysql 操作mysql数据库(实例讲解)

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#author: 陈月白 
#_blogs: http://www.cnblogs.com/chenyuebai/ 
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# -*- coding: utf-8 -*-
class MysqlTools():
 """
 连接mysql
 库、表操作
 """
 def __init__(self,host,dbname,user,passwd,charset="utf8"):
 self.host = host
 self.dbname = dbname
 self.user = user
 self.passwd = passwd
 self.charset = charset

 def connectMysqlDatabase(self):
 """连接db"""
 try:
  #连接db
  connect = pymysql.connect(host=self.host,user=self.user,passwd=self.passwd,db=self.dbname,charset=self.charset)
  cursor = connect.cursor()
  databaseConnectInfo = self.user + "@" + "self.host" + "/" + self.dbname
  print("INFO:connect database %s success."%databaseConnectInfo)
  return connect,cursor
 except:
  traceback.print_exc()
  print("ERROR:FUNCTION connectMysqlDatabase connect mysql database failed.")

 def executeSqlLine(self,sqlLine):
 """执行单条sql语句"""
 if sqlLine and isinstance(sqlLine,str):
  print("INFO:now start connect mysql dababase.")
  connect,cursor = self.connectMysqlDatabase()
  executeResult = ""
  try:
  #游标执行sql
  cursor.execute(sqlLine)
  executeResult = cursor.fetchall() #获取所有执行结果
  cursor.close()    #关闭游标
  connect.commit()   #确认提交
  print("INFO:execute sql sucess. sqlLine = ", sqlLine)
  except Exception as e:
  print("ERROR：execute sql failed.errorInfo =",e)
  print("ERROR:FUNCTION executeSql execute failed.sqlLine =",sqlLine)
  connect.rollback()   #回滚db
  return str(e) + " sqlLine = " + sqlLine
  #断开连接
  connect.close()
  print("INFO:connect closed.n")
  return executeResult
 else:
  print("ERROR:param sqlLine is empty or type is not str.sqlLine = ",sqlLine)

 def executeBatchSql(self,sqlList):
 """
 批量执行sql
 exp: executeBatchSql([sql_1,
    sql_2,
    sql_3,
    ......
    ])
 """
 finalResultList = []
 if sqlList:
  for sql in sqlList:
  executeResult = self.executeSqlLine(sql)
  finalResultList.append(executeResult)
 else:
  print("ERROR:param sqlList is empty.")
 return finalResultList

# -*- coding: utf-8 -*-
from my_code.work_tools import WorkTools
mysql = WorkTools.MysqlTools("localhost","testdbname","rootuername","passwd")
#执行单行sql
ret1 = mysql.executeSqlLine("show databases")
#批量执行
ret2 = mysql.executeBatchSql([
       "show databases",
       "show tables",
       "update students_info set name = '王大花D' where id = 2",
       "select * from students_info",
       "error sql test"  #异常sql测试
        ])
print("ret1 = ",ret1)
print("---------------------")
for i in ret2:
 print(i)