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  • 数据库连接池的sqlhelper

    import pymysql
    import threading
    from DBUtils.PooledDB import PooledDB
    
    """
    storage = {
        1111:{'stack':[]}
    }
    """
    
    class SqlHelper(object):
        def __init__(self):
            self.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链接,0表示不创建
                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
                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='222',
                database='cmdb',
                charset='utf8'
            )
            self.local = threading.local()
    
        def open(self):
            conn = self.pool.connection()
            cursor = conn.cursor()
            return conn, cursor
    
        def close(self, cursor, conn):
            cursor.close()
            conn.close()
    
        def fetchall(self, sql, *args):
            """ 获取所有数据 """
            conn, cursor = self.open()
            cursor.execute(sql, args)
            result = cursor.fetchall()
            self.close(conn, cursor)
            return result
    
        def fetchone(self, sql, *args):
            """ 获取所有数据 """
            conn, cursor = self.open()
            cursor.execute(sql, args)
            result = cursor.fetchone()
            self.close(conn, cursor)
            return result
    
        def __enter__(self):
            conn,cursor = self.open()
            rv = getattr(self.local,'stack',None)
            if not rv:
                self.local.stack = [(conn,cursor),]
            else:
                rv.append((conn,cursor))
                self.local.stack = rv
            return cursor
    
        def __exit__(self, exc_type, exc_val, exc_tb):
            rv = getattr(self.local,'stack',None)
            if not rv:
                # del self.local.stack
                return
            conn,cursor = self.local.stack.pop()
            cursor.close()
            conn.close()
    
    db = SqlHelper()
    
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  • 原文地址:https://www.cnblogs.com/ciquankun/p/12033265.html
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