数据连接
Pymysql
- 安装
- pip install PyMySQL
- # -*- coding: utf-8 -*-
- import pymysql
- conn = pymysql.connect(host="192.168.32.71", user="root",password="redhat",database="my_sql",charset="utf8")
- cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
-
- sql = "select * from name"
- res = cursor.execute(sql)
- print(cursor.fetchall())
-
- # [{"name": "peach", "id": 1, "age": 25}, {"name": "taoiz", "id": 2, "age": 23}]
- cursor.close()
- conn.close()
数据库连接池" title="数据库连接池">数据库连接池DBUtils
- 安装
- pip install DBUtils -i https://pypi.douban.com/simple
-
-
- # 数据库连接池
- # -*- coding: utf-8 -*-
- import pymysql
- from DBUtils.PooledDB import PooledDB
- POOL = PooledDB(
- creator=pymysql, # 使用链接数据库的模块
- maxconnections=6, # 连接池允许的最大连接数,0和None表示不限制连接数
- mincached=2, # 初始化时,链接池中至少创建的空闲的链接,0表示不创建
- maxcached=5, # 链接池中最多闲置的链接,0和None不限制
- maxshared=3, # 链接池中最多共享的链接数量,0和None表示全部共享。PS: 无用,因为pymysql和MySQLdb等模块的 threadsafety都为1,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。
-
- blocking=True, # 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
- maxusage=None, # 一个链接最多被重复使用的次数,None表示无限制
- setsession=[], # 开始会话前执行的命令列表。如:["set datestyle to ...", "set time zone ..."] 比如设置数据库的开始时间 set firstday=3
-
- ping=0,
- # ping MySQL服务端,检查是否服务可用。
- # 如:0 = None = never,
- # 1 = default = whenever it is requested,
- # 2 = when a cursor is created,
- # 4 = when a query is executed,
- # 7 = always
- host="192.168.32.71",
- port=3306,
- user="root",
- password="redhat",
- charset="utf8",
- db="my_sql"
- )
-
- # 使用
- conn = POOL.connection() # pymysql - conn
- cur = conn.cursor(cursor=pymysql.cursors.DictCursor)
-
- res = cur.execute("select * from name")
- print(cur.fetchall())
- # [{"name": "peach", "id": 1, "age": 25}, {"name": "taoiz", "id": 2, "age": 23}]
-
- # 关闭
- cur.close()
- conn.close()
自己封装的sqlhelper
- from dbpool import POOL
- import pymysql
-
- def create_conn():
- conn = POOL.connection()
- cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
- return conn,cursor
-
- def close_conn(conn,cursor):
- cursor.close()
- conn.close()
-
- def insert(sql,args):
- conn,cursor = create_conn()
- res = cursor.execute(sql,args)
- conn.commit()
- close_conn(conn,cursor)
- return res
-
- def fetch_one(sql,args):
- conn,cursor = create_conn()
- cursor.execute(sql,args)
- res = cursor.fetchone()
- close_conn(conn,cursor)
- return res
-
- def fetch_all(sql,args):
- conn,cursor = create_conn()
- cursor.execute(sql,args)
- res = cursor.fetchall()
- close_conn(conn,cursor)
- return res
-
- # sql = "insert into users(name,age) VALUES (%s, %s)"
-
- # insert(sql,("mjj",9))
-
- sql = "select * from users where name=%s and age=%s"
-
- print(fetch_one(sql,("mjj",9)))
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