版本环境

python 3.7DBUtils 1.3mysqlclient 1.4.6

连接池初始化

pool = PooledDB(creator=MySQLdb, mincached=0, maxcached=0, maxshared=0, maxconnections=0, blocking=False, maxusage=None, setsession=None, reset=True, failures=None, ping=1, *args, **kwargs)

参数说明

creator

#creator => 任何符合DB-API 2.0规范的函数或者兼容的数据库模块mincached

#mincached => 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

#maxcached => 链接池中最大闲置的链接数(0和None不限制)maxshared

#maxshared => maximum number of shared connections (0 or None means all connections are dedicated) When this maximum number is reached, connections are shared if they have been requested as shareablemaxconnections

#maxconnections => 允许的最大链接数(0或None表示不限制)blocking

#blocking => 链接池没有可用链接后，是否阻塞等待。 True表示阻塞等待,直到获取到链接; False不等待,抛异常退出maxusage

#maxusage => 同一个链接最多被重复使用的次数(0和None表示无限制）setsession

#setsession => 可选的会话命令：开始会话前执行的命令列表。例如["set datestyle to…"，"set time zone…"]reset

#reset => 当连接放回池中时，重置连接的方式，默认为True。 False或者None表示使用begin()开启了事务的链接，会执行回滚; 安全起见,建议使用True,当为True时表示所有链接都执行回滚操作failures

#failures => 当默认的(OperationalError,InternalError)异常不能满足要求时, 可以自定义抛出异常:默认为None; 自定义为传入的为tuple或者issubclass(failures, Exception)ping

#ping => 检查连接是否仍然处于活动状态的方式 0 = None = never, 1 = default = whenever fetched from the pool, 2 = when a cursor is created, 4 = when a query is executed, 7 = always, and all other bit combinations of these valuesargs, kwargs

#args, kwargs => 传递给creator的参数

使用

# -*- coding: utf-8 -*-# @Time : 2020/1/26 0026 20:28# @Email : lofish@foxmail.com(撸小鱼)import MySQLdbimport MySQLdb.cursorsfrom DBUtils.PooledDB import PooledDBimport datetimeclass DbManager(object): def __init__(self, host, port, db_name, user_name, password): cmds = ["set names utf8mb4;"] conn_args = {'host': host, 'port': port, 'db': db_name, 'user': user_name, 'passwd': password, 'charset': 'utf8', 'cursorclass': MySQLdb.cursors.DictCursor } # 初始化时，链接池中至少创建的空闲的链接，0表示不创建,mincached: 5 # 链接池中最大闲置的链接数(0和None不限制): 20 self._pool = PooledDB(MySQLdb, mincached=5, maxcached=20, setsession=cmds, **conn_args) def connection(self): return self._pool.connection()_db_manager = Nonedef create_db_manager(host, port, dbname, username, password): global _db_manager if _db_manager is None: _db_manager = DbManager(host, port, dbname, username, password) return _db_manager