MySQL 使用连接池封装pymysql

备注:1,记得先修改连接的数据库哦,(用navicat更方便一点);2,分开两个py文件写入,运行sqlhelper.py文件

一、在utils.py中写

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=1, # 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='',
database='ziji',
charset='utf8'
)


二、在sqlhelper.py中写入:
from utils import POOL
import pymysql


def create_conn():
conn = POOL.connection()
cursor = conn.cursor(pymysql.cursors.DictCursor)
return conn, cursor


def close_conn(conn, cursor):
conn.close()
cursor.close()


def select_one(sql, args):
conn, cur = create_conn()
cur.execute(sql, args)
result = cur.fetchone()
close_conn(conn, cur)
return result


def select_all(sql, args):
conn, cur = create_conn()
cur.execute(sql, args)
result = cur.fetchall()
close_conn(conn, cur)
return result


def insert_one(sql, args):
conn, cur = create_conn()
result = cur.execute(sql, args)
conn.commit()
close_conn(conn, cur)
return result


def delete_one(sql,args):
conn,cur = create_conn()
result = cur.execute(sql,args)
conn.commit()
close_conn(conn,cur)
return result

def update_one(sql,args):
conn,cur = create_conn()
result = cur.execute(sql,args)
conn.commit()
close_conn(conn,cur)
return result



# sql = "insert into stu(id,name,age) VALUE (%s,%s,%s)" #增加
# res = insert_one(sql, [2,"飞机", 28])
# print(res)

# sql = "delete from stu where name = %s" #删除
# res = delete_one(sql, "哪吒")
# print(res)

# sql = "select * from stu" #查询全部
# res = select_all(sql, [])
# print(res)

# sql = "select * from stu where name=%s" #查询一条
# res = select_one(sql, "赵振伟")
# print(res)



# sql = " UPDATE stu set name=%s where name = %s" #更新
# res = update_one(sql,("坦克","飞机"))
# print(res)

转载自:https://www.cnblogs.com/zzw731862651/articles/9605308.html