pip3 install -i https://pypi.douban.com/simple DBUtils

from DBUtils.PooledDB import PooledDB

import pymysql

#

class Config:

    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 ..."]

        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='127.0.0.1',

        port=3306,

        user='root',

        password='密码',

        database='DBU',

        charset='utf8'

    )

import pymysql

from settings import Config

con = Config.POOL.connection()

cursor = con.cursor(cursor=pymysql.cursors.DictCursor)

sql = "select name, line from userinfo where name=%s"

args = 'tom'

cursor.execute(sql, (args,))

data = cursor.fetchall()

print(data)

cursor.close()

con.close()

import pymysql

from settings import Config

def connect_database(sql, args):

    con = Config.POOL.connection()

    cursor = con.cursor(cursor=pymysql.cursors.DictCursor)

    cursor.execute(sql, (args,))

    data = cursor.fetchall()

    # print(data)

    cursor.close()

    con.close()

    return data

sql = "select name, line from userinfo where name=%s"

args = 'tom'

ret = connect_database(sql, args)

print(ret)

import pymysql

from settings import Config

def db_connect():

    con = Config.POOL.connection()

    cursor = con.cursor(cursor=pymysql.cursors.DictCursor)

    return con, cursor

def db_connect_close(cursor, con):

    cursor.close()

    con.close()

def fetch_all(sql, args):

    con, cursor = db_connect()

    # con = Config.POOL.connection()

    # cursor = con.cursor(cursor=pymysql.cursors.DictCursor)

    cursor.execute(sql, (args,))

    data = cursor.fetchall()

    # print(data)

    db_connect_close(cursor, con)

    # cursor.close()

    # con.close()

    return data

# sql = "select name, line from userinfo where name=%s"

# args = 'tom'

#

#

# ret = fetch_all(sql, args)

# print(ret)

from xx import fetch_all

sql = "select name, line from userinfo where name=%s"

args = 'tom'

ret = fetch_all(sql, args)

print(ret)