Django框架操作数据库的两种方式

Django操作数据库的前提操作是成功连接数据库，详情见上篇：https://www.cnblogs.com/kristin/p/10791358.html

• Django查询数据库的方式一

from django.db import connection
from django.http import HttpResponse
def research(request):
    cursor = connection.cursor()
    cursor.execute("SELECT * FROM `user` WHERE `status` = '3' AND `created` <= '1557331200' AND `finished` >= '1557417599'")
    sql = cursor.fetchall()
    return HttpResponse(sql)
    
# shell模式打印输出结果的类型，print(type(sql)),结果为<class 'tuple'>  

• Django查询数据库的方式二

from django.db import connection
from quicktool.models import User
from django.http import HttpResponse
def research(request):
    sql = User.objects.all().filter(status=3).filter(created__lte=1557331200).filter(finished__gte=1557417599).values_list()
    #或sql = User.objects.all().filter(status=3).filter(created__lte=1557331200).filter(finished__gte=1557417599).values()
    return HttpResponse(sql)
    
# values_list()迭代时返回元组tuple；values()迭代时返回字典dict

　　

上述两种方式查询的sql语句是一致的：

注：QuerySet对象可用.query.__str__()或 .query属性打印执行的sql语句

sql = User.objects.all().filter(status=3).filter(created__lte=1557331200).filter(finished__gte=1557417599)
cursor.execute("SELECT * FROM `user` WHERE `status` = '3' AND `created` <= '1557331200' AND `finished` >= '1557417599' ")