小编noo*_*per的帖子

我已经定义了类声明:

from mongoengine import *
class TickDataDocument(Document):
"""
"""
    instrument_id = StringField(max_length=10, unique=True, required=True)
    tick_data = ReferenceField(TickDocument)


class TickDocument(Document):
"""
"""
    price = DecimalField(precision=2, required=True) 
    volume = LongField(required=True)  
    turnover = DecimalField(precision=2, required=True)  
    update_time = DateTimeField(unique=True, required=True)

我想在一段时间内查询update_time.

 TickDataDocument.objects(instrument_id="fa1100").filter(tick_data__ update_time__lt =datetime.datetime(2013,9,3))

但是我得到了错误:

mongoengine.errors.InvalidQueryError:无法在mongoDB中执行连接:tick_data__update_time

我怎么能有五个解决方案来查询mongoengine中的内部引用字段.

我想更改 numpy 列数据类型，但是当我替换原始 numpy 列时，dtype 不会成功更改。

import numpy as np 

arraylist =[(1526869384.273246, 0, 'a0'),
(1526869385.273246, 1, 'a1'),
(1526869386.273246, 2, 'a2'),
(1526869387.273246, 3, 'a3'),
(1526869388.273246, 4, 'a4'),
(1526869389.273246, 5, 'a5'),
(1526869390.273246, 6, 'a6'),
(1526869391.273246, 7, 'a7'),
(1526869392.273246, 8, 'a8'),
(1526869393.273246, 9, 'a9'),
(1526869384.273246, 0, 'a0'),
(1526869385.273246, 1, 'a1'),
(1526869386.273246, 2, 'a2'),
(1526869387.273246, 3, 'a3'),
(1526869388.273246, 4, 'a4'),
(1526869389.273246, 5, 'a5'),
(1526869390.273246, 6, 'a6'),
(1526869391.273246, 7, 'a7'),
(1526869392.273246, 8, 'a8'),
(1526869393.273246, 9, 'a9')]

array =  np.array(arraylist)

array.dtype

dtype('<U32')

array[:,0]=array[:,0].astype("float64")
array[:,0].dtype 

>>> dtype('<U32') …

Linux版本:Ubuntu 14.04.1 LTS服务器版本:5.7.11 MySQL社区服务器(GPL)从以下链接下载:http://dev.mysql.com/downloads/repo/apt/

当我尝试运行时,mysql_secure_installation 我设置了密码并重新加载完成的所有任务.但是当我尝试登录mysql时,它不需要root用户的密码.

>>>mysql 


mysql> select * from user;
+-----------+-----------+-------------+-------------+-------------+----    ---------+-------------+-----------+-------------+---------------+--------------+-----------+------------+-----------------+------------+------------+--------------+------------+-----------------------+------------------+--------------+-----------------+------------------+------------------+----------------+---------------------+--------------------+------------------+------------+--------------+------------------------+----------+------------+-------------+--------------+---------------+-------------+-----------------+----------------------+-----------------------+-------------------------------------------+------------------+-----------------------+-------------------+----------------+
| Host      | User      | Select_priv | Insert_priv | Update_priv | Delete_priv | Create_priv | Drop_priv | Reload_priv | Shutdown_priv | Process_priv | File_priv | Grant_priv | References_priv | Index_priv | Alter_priv | Show_db_priv | Super_priv | Create_tmp_table_priv | Lock_tables_priv | Execute_priv | Repl_slave_priv | Repl_client_priv | Create_view_priv | Show_view_priv | Create_routine_priv | Alter_routine_priv | Create_user_priv | Event_priv | Trigger_priv | Create_tablespace_priv | …