为每个查询打开一个新的MySQL游标是否很慢?

当然,将连接重新连接数千次将需要更多的时间。您最好将其设置为类的属性,如下所示:

class yourClass():
    self.db = ...
    self.cursor = self.con.Cursor()

    # do something
    def fetch_data(self, query):
        try:
            if self.cursor:
                self.cursor.execute(query)
            else:
                raise OperationalError
            return self.cursor.fetchall()
        except OperationalError as e:
            self.db = fetchDb()
            self.db.autocommit(True)
            print 'reconnecting and trying again...'
            return fetch_data(query)