python-django-自定义查询Q函数和F函数

 

 

 

 数据库：

 

 

def page_q(request):
    """Q函数的使用"""
    #查询username和nickname都是zhangsan
    user_list = WeiboUser.objects.filter(username='zhangsan')
    user2_list = WeiboUser.objects.filter(nickname='zhangsan')
    print(user_list)
    print(user2_list)

    # OR |
    name = request.GET.get('name',None)#通过URL进行参数得传递，默认无
    query = Q(username=name) | Q(nickname=name)
    user_listQ = WeiboUser.objects.filter(query)
    print(user_listQ)

    print('SSSSSSSSSSSSSSSSSSSSSSS')
    # AND &
    #查询名字和昵称是某某得用户
    #username 按用户名查血
    username = request.GET.get('username',None)
    # nickname 按昵称擦化学
    nickname = request.GET.get('nickname',None)
    query = Q()#避免下面不进入if语句里面
    if username is not None:
        query = query & Q(username=username)
    if nickname is not None:
        query = query & Q(nickname=nickname)

    user_list_q2 = WeiboUser.objects.filter(query)
    print(user_list_q2.count())

    return HttpResponse('dddd')

 

URL：
http://127.0.0.1:8000/weibo/Q/?nickname=zhangsan


结果为
[08/May/2020 22:32:41] "GET /weibo/Q/?username=zhangsan HTTP/1.1" 200 4
1
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:zhangsan pk:4,nickname:qq>]>
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:duser1 pk:9,nickname:zhangsan>, <WeiboUser: User:duser2 pk:10,nickname:zhangsan>]>
<QuerySet []>
SSSSSSSSSSSSSSSSSSSSSSS
3
[08/M

 

URL 
http://127.0.0.1:8000/weibo/Q/?username=zhangsan


结果：
[08/May/2020 22:32:57] "GET /weibo/Q/?nickname=zhangsan HTTP/1.1" 200 4
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:zhangsan pk:4,nickname:qq>]>
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:duser1 pk:9,nickname:zhangsan>, <WeiboUser: User:duser2 pk:10,nickname:zhangsan>]>
<QuerySet []>
SSSSSSSSSSSSSSSSSSSSSSS
2

 

URL：
http://127.0.0.1:8000/weibo/Q/?name=zhangsan

结果：
[08/May/2020 22:38:22] "GET /weibo/Q/?username=zhangsan HTTP/1.1" 200 4
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:zhangsan pk:4,nickname:qq>]>
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:duser1 pk:9,nickname:zhangsan>, <WeiboUser: User:duser2 pk:10,nickname:zhangsan>]>
<QuerySet [<WeiboUser: User:zhangsan pk:3,nickname:zhangsan>, <WeiboUser: User:zhangsan pk:4,nickname:qq>, <WeiboUser: User:duser1 pk:9,nickname:zhangsan>, <WeiboUser: User:duser2 pk:10,nickname:zhangsan>]>
SSSSSSSSSSSSSSSSSSSSSSS
106


由于这里没有传入username 和nickname所以查询为没条件，所以全部得数据都查询出来了

 

 

 

 

import threading

from django.db.models import F

from weibo.models import WeiboUser

class ChangeThread(threading.Thread):
    """改变用户的状态"""
    def __init__(self,max_count=100,*args,**kwargs):
        super().__init__(*args,**kwargs)
        self.max_count = max_count

    def run(self):
        count = 0
        user = WeiboUser.objects.get(pk=2)
        while True:
            if count >= self.max_count:
                break
            print(self.getName(),count)
            # user.status+=1
            user.status = F('status') + 1
            #F函数表示每次操作都要去数据库查询出数据进行炒作
            user.save()
            count +=1

def main():
    t1 = ChangeThread(max_count=800)
    t2 = ChangeThread(max_count=500)
    t1.start()
    t2.start()
    t1.join()
    t2.join()