python连接mysql与方法的封装

             1
            import
             pymysql

             2
             3
            class
             Model(object):

             4
            def
            __init__(self, username=‘root‘, password=‘123456‘, database=‘demo‘, 
 5                  port=3306, host=‘localhost‘):
 6# 创建连接 7         self.connection = pymysql.connect(user=username, password=password, database=database,
 8                                           port=port, host=host, cursorclass=pymysql.cursors.DictCursor)
 9# 创建游标10         self.cursor = self.connection.cursor()
1112# 查询所有数据13def fetchall(self, sql):
14try:
15             self.__execute(sql)
16return self.cursor.fetchall()
17except Exception as error:
18print(error)
1920# 查询多条数据21def fetchmany(self, sql, size=1):
22try:
23             self.__execute(sql)
24return self.cursor.fetchmany(size)
25except Exception as error:
26print(error)
2728# 查询一条数据29def fetchone(self, sql):
30try:
31             self.__execute(sql)
32return self.cursor.fetchone()
33except Exception as error:
34print(error)
3536# 增删改的方法37def change(self, sql):
38try:
39             self.__execute(sql)
40            self.connection.commit()
41except Exception as error:
42print(error)
4344# 执行的私有方法45def__execute(self, sql):
46        self.cursor.execute(sql)
4748# 关闭连接和游标49def__del__(self):
50        self.connection.close()
51         self.cursor.close()

             1
            from data_connect import model
 2 3# 实例化Model类 4 employee = model.Model()
 5 res = employee.fetchall(‘select nickname from employee where job="头领"‘)[0]
 6 res1 = employee.fetchmany(‘select nickname from employee where job="头领"‘, 2)
 7 res2 = employee.fetchone(‘select nickname from employee where name = "宋江"‘)
 8# print(res2) 910# 插入一条语句11 employee.change(‘insert into employee (name)values ("关羽")‘)
12# 删除一条语句13 employee.change(‘delete from employee where name="关羽"‘)
14# 更新一条语句15# obj.change(‘update employee set name="张飞"where id=8004‘)