1.新建Model 1.users数据 1.在apps/users/models.py中: from datetime import datetime from django.db import models from django.contrib.auth.models import AbstractUser # Create your models here. class UserProfile(AbstractUser): """ 管理员 ""&qu
引入MQ话题 可能很多人有疑惑:MQ到底是什么?哪些场景下要使用MQ? 前段时间安装了RabbitMQ,现在就记录下自己的学习心得吧.首先看段程序: class Program { static void Main(string[] args) { new Thread(Write).Start(); new Thread(Write).Start(); new Thread(Write).Start(); new Thread(Write).Start(); } public static v
当没有用 EXISTS 引入子查询时,在选择列表中只能指定一个表达式.比如 select * from T_Employee where FNumber not in ( select top 5* from T_Employee order by FSalary desc)order by FSalary 在sql中执行出现错误 更正:select * from T_Employee where FNumber not in (select top 5 FNumber from T_Em