Question

在我的python脚本中，我订阅了一个Web套接字。每当收到数据时，我都会将此数据插入MySQL数据库。每秒大约有100-200个查询。问题是它工作了一段时间，然后它给出了错误＆＃34;错误2006：MySQL服务器已经消失了＃34; 我将Max_allowed_packets增加到512M。但它没有用。

这是我的代码。

def db_entry(threadName, _data):
_time = time.strftime('%Y-%m-%d %H:%M:%S')


#print ("starting new thread...")

for data in _data:
    #print (data)
    sql = "INSERT INTO %s (Script_Name, Lot_Size, Date, Time, Last_Price, Price_Change, Open,High, Low, Close, Volume, Buy_Quantity,  Sell_Quantity) VALUES('%s','%s','%s','%s','%s','%s','%s','%s','%s','%s','%s','%s','%s')" %("_" + str(data['instrument_token']), data['instrument_token'], 1, datetime.datetime.today().strftime("%Y-%m-%d"), _time, data['last_price'], data['change'], data['ohlc']['open'], data['ohlc']['high'], data['ohlc']['low'], data['ohlc']['close'], data['volume'], data['buy_quantity'], data['sell_quantity'])


    cursor.execute(sql)
    # Commit your changes in the database
    db.commit()

def on_tick(tick, ws):
thread_name = "Thread" + str(thread_count + 1)
try:
    _thread.start_new_thread(db_entry,(thread_name,tick, ))
except exception as e:
    print (e)
    raise

def on_connect(ws):
# Subscribe to a list of instrument_tokens (RELIANCE and ACC here).
ws.subscribe(instrument_token)

# Set RELIANCE to tick in `full` mode.
ws.set_mode(ws.MODE_FULL,instrument_token)

# Assign the callbacks.
kws.on_tick = on_tick
kws.on_connect = on_connect


kws.enable_reconnect(reconnect_interval=5, reconnect_tries=50)

# Infinite loop on the main thread. Nothing after this will run.
# You have to use the pre-defined callbacks to manage subscriptions.
kws.connect()

提前致谢。：）

Answer 1

MySQL开发人员文档提供的documentation在这一点上非常明确。可能的情况是，其中一些MySQL查询运行速度比其他查询慢，因为他们正在等待轮到他们插入数据。如果他们等待太久，MySQL将关闭他们的连接。默认情况下，MySQL的wait_timeout为8小时（28800秒）。 MySQL配置是否经过调整？为MySQL分配了多少硬件？

通常，查看所有超时配置。阅读并理解它们。不要简单地复制和粘贴所有性能调整博客，如博客。

Answer 2

最后，它已经解决了。我保持数据库连接打开，这导致了问题。我在触发查询时关闭数据库连接。当想再次插入东西时再次打开。

Answer 3

您需要使用自己的连接处理方法创建对象。我用它并运作良好。

class DB():
def __init__(self, **kwargs):
    self.conn = MySQLdb.connect(‘host’, ‘user’, ‘pass’, ‘db’)
    try:
        if (self.conn):
            status = "DB init success"
        else:
            status = "DB init failed"
        self.conn.autocommit(True)
        # self.conn.select_db(DB_NAME)
        self.cursor = self.conn.cursor()
    except Exception as e:
        status = "DB init fail %s " % str(e)

def execute(self, query):
    try:
        if self.conn is None:
            self.__init__()
        else:
            self.conn.ping(True)
            self.cursor.execute(query)
        return self.cursor.fetchall()
    except Exception as e:
        import traceback
        traceback.print_exc()
        # error ocurs,rollback
        self.conn.rollback()
        return False

用法

data = DB().execute("SELECT * FROM Users")

print(data)

MySQL服务器已经消失了python MySQLdb

3 个答案: