python操作数据库

  1 import pymysql
  2 from DBUtils.PooledDB import PooledDB
  3 
  4 
  5 class SQLHandler(object):
  6     def __init__(self, host, port, db_username, db_password, db_name):
  7         # pip install --default-timeout=100 dbutils
  8         self.pool = PooledDB(
  9             # 使用链接数据库的模块import pymysql
 10             creator=pymysql,
 11             # 连接池允许的最大连接数，0和None表示不限制连接数
 12             maxconnections=6,
 13             # 初始化时，链接池中至少创建的空闲的链接，0表示不创建
 14             mincached=2,
 15             # 链接池中最多闲置的链接，0和None不限制
 16             maxcached=5,
 17             # 链接池中最多共享的链接数量，0和None表示全部共享。
 18             # 因为pymysql和MySQLdb等模块的 threadsafety都为1，
 19             # 所有值无论设置为多少，maxcached永远为0，所以永远是所有链接都共享。
 20             maxshared=3,
 21             # 连接池中如果没有可用连接后，是否阻塞等待。True，等待；False，不等待然后报错
 22             blocking=True,
 23             # 一个链接最多被重复使用的次数，None表示无限制
 24             maxusage=None,
 25             # 开始会话前执行的命令列表。如：["set datestyle to ...", "set time zone ..."]
 26             setsession=[],
 27             # ping MySQL服务端，检查是否服务可用。
 28             #  如：0 = None = never, 1 = default = whenever it is requested,
 29             # 2 = when a cursor is created, 4 = when a query is executed, 7 = always
 30             ping=0,
 31 
 32             # 数据库信息
 33             host=host,
 34             port=int(port),
 35             user=db_username,
 36             password=db_password,
 37             database=db_name,
 38             charset=‘utf8‘
 39         )
 40 
 41     def create_conn_cursor(self):
 42         # 创建连接
 43         conn = self.pool.connection()
 44         # 创建游标
 45         cursor = conn.cursor(pymysql.cursors.DictCursor)
 46         # 返回conn, cursor
 47         return conn, cursor
 48 
 49     def fetch_one(self, sql, args):
 50         conn, cursor = self.create_conn_cursor()
 51         cursor.execute(sql, args)
 52         result = cursor.fetchone()
 53         cursor.close()
 54         conn.close()
 55         return result
 56 
 57     def fetch_many(self, sql, args):
 58         conn, cursor = self.create_conn_cursor()
 59         cursor.execute(sql)
 60         result = cursor.fetchmany(args)
 61         cursor.close()
 62         conn.close()
 63         return result
 64 
 65     def fetch_all(self, sql, args):
 66         conn, cursor = self.create_conn_cursor()
 67         cursor.execute(sql, args)
 68         result = cursor.fetchall()
 69         cursor.close()
 70         conn.close()
 71         return result
 72 
 73     def insert_one(self, sql, args):
 74         conn, cursor = self.create_conn_cursor()
 75         res = cursor.execute(sql, args)
 76         conn.commit()
 77         print(res)
 78         conn.close()
 79         return res
 80 
 81     def insert_many(self, sql, args):
 82         conn, cursor = self.create_conn_cursor()
 83         res = cursor.executemany(sql, args)
 84         conn.commit()
 85         print(res)
 86         conn.close()
 87         return res
 88 
 89     def update(self, sql, args):
 90         conn, cursor = self.create_conn_cursor()
 91         res = cursor.execute(sql, args)
 92         conn.commit()
 93         print(res)
 94         conn.close()
 95         return res
 96 
 97     def delete(self, sql, args):
 98         conn, cursor = self.create_conn_cursor()
 99         res = cursor.execute(sql, args)
100         conn.commit()
101         print(res)
102         conn.close()
103         return res

 1 from SQLHandler import SQLHandler
 2 
 3 if __name__ == ‘__main__‘:
 4     # 连接mysql
 5     sqlhelper = SQLHandler("192.168.1.6", 3306, "root", "root", "datatest")
 6     ## 查询
 7     # 指定列名查询
 8     # ret = sqlhelper.fetch_all("select * from user where id=%s",(2))
 9     # ret = sqlhelper.fetch_all("select * from user where name=%s",(‘apollo‘))
10     # 显示查询结果第一条
11     # ret = sqlhelper.fetch_one("select * from user",None)
12     # 显示查询结果前两条
13     # ret = sqlhelper.fetch_many("select * from user",(2))
14     # 显示查询结果全部
15     # ret = sqlhelper.fetch_all("select * from user", None)
16     # for (index, item) in enumerate(ret, 1):
17     #     print(index, item)
18 
19 
20     ## 插入
21     # 插入一条数据
22     # 方式1：
23     # ret = sqlhelper.insert_one("insert into user VALUES (%s,%s,%s)",(10,"litch",56))
24     # 方式2：
25     #  ret = sqlhelper.insert_one("insert into user (name,age)VALUES (%s,%s)",("banana",12))
26     # 插入多条数据
27     data = []
28     for index in range(0,100000):
29         by = str(index)
30         name = "name2"+by
31         temp = (name,0,16)
32         data.append(temp)
33     sql = ‘insert into user(name,six,age) values(%s,%s,%s);‘
34     ret = sqlhelper.insert_many(sql,data)
35 
36 
37     ## 更新
38     # ret = sqlhelper.update("update user SET name=%s WHERE id=%s",("Smith",1))
39 
40 
41     ## 删除
42     # ret = sqlhelper.delete("delete from user where name=%s;",[("jack88")])
43     print(ret)