import pymysql class MysqlHelper(object): conn = None def __init__(self, host, username, password, db, charset=‘utf8‘, port=3306): self.host = host self.username = username self.password = password self.db = db self.charset = charset self.port = port def connect(self): self.conn = pymysql.connect(host=self.host, port=self.port, user=self.username, password=self.password, db=self.db, charset=self.charset) self.cursor = self.conn.cursor() def close(self): self.cursor.close() self.conn.close() def get_one(self, sql, params=()): result = None try: self.connect() self.cursor.execute(sql, params) result = self.cursor.fetchone() self.close() except Exception as e: print(e) return result def get_all(self, sql, params=()): list_data = () try: self.connect() self.cursor.execute(sql, params) list_data = self.cursor.fetchall() self.close() except Exception as e: print(e) return list_data def insert(self, sql, params=()): return self.__edit(sql, params) def update(self, sql, params=()): return self.__edit(sql, params) def delete(self, sql, params=()): return self.__edit(sql, params) def __edit(self, sql, params): count = 0 try: self.connect() count = self.cursor.execute(sql, params) self.conn.commit() self.close() except Exception as e: print(e) return count def du(self,aa):#打开图片读入内存给变量 fp = open(aa, ‘rb‘) try: img = fp.read() except: print("图片打开出错") fp.close() return img def bu(self,aa,bname,id):#从数据表bname中读取对应ID图片并保存为文件名为aa sql=f"select tu from {bname} where id={id}" fp = open(aa, ‘wb‘) try: self.connect() self.cursor.execute(sql) self.conn.commit() fp.write(self.cursor.fetchone()[0]) self.close() except: print("图片读写出错") #aa=MysqlHelper("db4free.net","myabcd","******","数据库名称") aa=MysqlHelper("localhost","root","**********","testa") sql="select sjh from sjh limit 10" sql1="select sjh from sjh where sjh=‘13000290804‘" sql2="delete from sjh where sjh=‘13000290804‘" sql3="select table_name from information_schema.tables where table_schema=‘mys‘" sql4="SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = ‘mys‘" sql5="select table_name,column_name,column_comment from information_schema.columns where table_schema =‘mys‘ and table_name =‘sjh‘" #显示指定数据库指定表的字段名称 sql6="desc sjh" images=aa.du("222.jpg") sql7=f"insert into xsxx6 (xm,tu) values (‘张三‘,%s);" sql8=f"update xsxx6 set xm=‘李四‘,tu =%s where id=1;" args=(images) #显示指定的详细结构(字段名称 类型 长度) #aa.insert(sql8,args)#利用插入将图片存入表中 #aa.update(sql)#利用更新的方法将图片存入表中 aa.bu(‘1234.jpg‘,‘xsxx‘,5)