項目需求:瀏覽器中訪問django後端某一條url(如:127.0.0.1:8080/get_book/),實時朝數據庫中生成一千條數據並將生成的數據查詢出來,並展現到前端頁面css
views.pyhtml
from django.shortcuts import render, HttpResponse, redirect from app01 import models def get_book(request): # for循環插入1000條數據 for i in range(1000): models.Book.objects.create(name='第%s本書'%i) book_queryset = models.Book.objects.all() # 將插入的數據再查詢出來 return render(request,'get_book.html',locals()) # 將查詢出來的數據傳遞給html頁面
urls.py前端
from django.conf.urls import url from app01 import views urlpatterns = [ url(r'^get_book/',views.get_book) ]
models.pyjquery
from django.db import models class get_book(models.Model): title = models.CharField(max_length=64)
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script> {% load static %} <link rel="stylesheet" href="{% static 'bootstrap-3.3.7-dist/css/bootstrap.min.css' %}"> <link rel="stylesheet" href="{% static 'dist/sweetalert.css' %}"> <script src="{% static 'bootstrap-3.3.7-dist/js/bootstrap.min.js' %}"></script> <script src="{% static 'dist/sweetalert.min.js' %}"></script> </head> <body> {% for book_obj in book_queryset %} <p>{{ book_obj.title }}</p> {% endfor %} </body> </html>
上述代碼書寫完畢後啓動django後端,瀏覽器訪問,會發現瀏覽器會有一個明顯的卡頓等待時間,這是由於後端在不停的操做數據庫,耗時較長,大概須要等待一段時間以後才能正常看到剛剛插入的1000條數據,很明顯這樣操做數據庫的效率過低,那有沒有一種方式是專門用來批量操做數據庫的呢?答案是確定的!數據庫
將views.py中原先的視圖函數稍做變化django
def get_book(request): l = [] for i in range(10000): l.append(models.Book(title='第%s本書'%i)) models.Book.objects.bulk_create(l) # 批量插入數據 return render(request,'get_book.html',locals())
代碼修改完畢以後其餘地方無需改動,重啓django項目瀏覽器從新訪問,你會立馬發現數據量增大十倍的狀況下頁面出現的速度比上面還快。bootstrap
bulk_create方法是django orm特意提供給咱們的方便批量操做數據庫的方式,效率很是高!!!後端