一, F Q
# F 使用查询条件的值 # # from django.db.models import F # models.Tb1.objects.update(num=F(\'num\')+1) # Q 构建搜索条件 from django.db.models import Q # con = Q() # # q1 = Q() # q1.connector = \'OR\' # q1.children.append((\'id\', 1)) # q1.children.append((\'id\', 10)) # q1.children.append((\'id\', 9)) # # q2 = Q() # q2.connector = \'OR\' # q2.children.append((\'c1\', 1)) # q2.children.append((\'c1\', 10)) # q2.children.append((\'c1\', 9)) # # con.add(q1, \'AND\') # con.add(q2, \'AND\') # # models.Tb1.objects.filter(con) # # from django.db import connection # cursor = connection.cursor() # cursor.execute("""SELECT * from tb where name = %s""", [\'Lennon\']) # row = cursor.fetchone()
Django基于Q 实现ajax请求数据库
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <style> .left{ float: left; } .clearfix:after{ content: \'.\'; clear: both; display: block; visibility: hidden; height: 0; } </style> </head> <body> <div class="condition"> <div class="item clearfix"> <div class="icon left" onclick="AddCondition(this);">+</div> <div class="left"> <select onchange="ChangeName(this);"> <option value="name">书名</option> <option value="book_type__caption">图书类型</option> <option value="price">价格</option> <option value="pages">页数</option> </select> </div> <div class="left"><input type="text" name="name" /></div> </div> </div> <div> <input type="button" onclick="Search();" value="搜索" /> </div> <div class="container"> </div> <script src="/static/jquery-1.9.1.min.js"></script> <script> function AddCondition(ths) { var new_tag = $(ths).parent().clone(); new_tag.find(\'.icon\').text(\'-\'); new_tag.find(\'.icon\').attr(\'onclick\', \'RemoveCondition(this);\'); $(ths).parent().parent().append(new_tag); } function RemoveCondition(ths) { $(ths).parent().remove(); } function ChangeName(ths) { var v = $(ths).val(); $(ths).parent().next().find(\'input\').attr(\'name\',v); } function Search() { var post_data_dict = {}; // 获取所有input的内容，提交数据 $(\'.condition input\').each(function () { // console.log($(this)[0]) var n = $(this).attr(\'name\'); var v = $(this).val(); var v_list = v.split(\'，\'); post_data_dict[n] = v_list; }); console.log(post_data_dict); var post_data_str = JSON.stringify(post_data_dict); $.ajax({ url: \'/index/\', type: \'POST\', data: { \'post_data\': post_data_str}, dataType: \'json\', success: function (arg) { // 字符串 "<table>" + if(arg.status){ var table = document.createElement(\'table\'); table.setAttribute(\'border\',1); // [{,name,pubdate,price,caption},] $.each(arg.data, function(k,v){ var tr = document.createElement(\'tr\'); var td1 = document.createElement(\'td\'); td1.innerText = v[\'name\']; var td2 = document.createElement(\'td\'); td2.innerText = v[\'price\']; var td3 = document.createElement(\'td\'); td3.innerText = v[\'book_type__caption\']; var td4 = document.createElement(\'td\'); td4.innerText = v[\'pubdate\']; tr.appendChild(td1); tr.appendChild(td2); tr.appendChild(td3); tr.appendChild(td4); table.appendChild(tr); }); $(\'.container\').empty(); $(\'.container\').append(table); }else{ alert(arg.message); } } }) } </script> </body> </html>
from django.shortcuts import render,HttpResponse from app01 import models # Create your views here. import json def test(request): # models.BookType.objects.create(caption=\'技术\') # models.BookType.objects.create(caption=\'文学\') # models.BookType.objects.create(caption=\'动漫\') # models.BookType.objects.create(caption=\'男人装\') # models.Book.objects.create(name=\'文艺复兴\',pages=\'100\',price=\'40\',pubdate=\'1992-11-2\',book_type_id=\'1\') # models.Book.objects.create(name=\'解密\',pages=\'80\',price=\'10\', pubdate=\'2016-6-10\',book_type_id=\'2\') # models.Book.objects.create(name=\'刀锋\',pages=\'50\',price=\'3\', pubdate=\'2014-02-16\',book_type_id=\'2\') # models.Book.objects.create(name=\'查令十字路84号\',pages=\'260\',price=\'40\',pubdate=\'1999-10-12\',book_type_id=\'3\') # models.Book.objects.create(name=\'红楼\',pages=\'1000\',price=\'500\', pubdate=\'1760-1-1\',book_type_id=\'3\') # models.Book.objects.create(name=\'将夜\',pages=\'2000\',price=\'300\', pubdate=\'2010-3-3\',book_type_id=\'1\') # models.Book.objects.create(name=\'mysql从删库到跑路\',pages=\'20\',price=\'10\',pubdate=\'1998-9-2\',book_type_id=\'4\') # models.Book.objects.create(name=\'马克思主义\',pages=\'50\',price=\'100\',pubdate=\'1937-3-3\',book_type_id=\'2\') return HttpResponse(\'ok\') import json from datetime import date from datetime import datetime from decimal import Decimal class JsonCustomEncoder(json.JSONEncoder): def default(self, field): if isinstance(field, datetime): return field.strftime(\'%Y-%m-%d %H:%M:%S\') elif isinstance(field, date): return field.strftime(\'%Y-%m-%d\') elif isinstance(field, Decimal): return str(field) else: return json.JSONEncoder.default(self, field) def index(request): if request.method == \'POST\': print(request.POST.get(\'post_data\',None)) ret = {\'status\': False, \'message\': \'\', \'data\':None} try: post_data = request.POST.get(\'post_data\',None) post_data_dict = json.loads(post_data) print(post_data_dict,type(post_data_dict)) # {\'name\': [\'11\', \'sdf\']，\'price\': [\'11\', \'sdf\']} # 构造搜索条件 from django.db.models import Q con = Q() for k,v in post_data_dict.items(): q = Q() q.connector = \'OR\' for item in v: print(v,type(v)) q.children.append((k, item)) con.add(q, \'AND\') """ ret = models.Book.objects.filter(con) print(ret) # queryset,[对象] from django.core import serializers data = serializers.serialize("json", ret) print(type(data),data) # 字符串 """ """ # ret = models.Book.objects.filter(con).values(\'name\',\'book_type__caption\')# 列表里面以字典的形式 # #ret = models.Book.objects.filter(con).values_list(\'name\', \'book_type__caption\')# 列表里面以元组的形式 # # li = list(ret) # data = json.dumps(li) # print(data,type(data)) """ result = models.Book.objects.filter(con).values(\'name\',\'price\',\'pubdate\',\'book_type__caption\') # ret = models.Book.objects.filter(con).values_list(\'name\', \'book_type__caption\') li = list(result) ret[\'status\'] = True ret[\'data\'] = li except Exception as e: ret[\'message\'] = str(e) ret_str = json.dumps(ret, cls=JsonCustomEncoder) return HttpResponse(ret_str) return render(request, \'index.html\')
from django.db import models # Create your models here. class Author(models.Model): name = models.CharField(max_length=20) age = models.IntegerField() class BookType(models.Model): caption = models.CharField(max_length=64) class Book(models.Model): name = models.CharField(max_length=64) pages = models.IntegerField() price = models.DecimalField(max_digits=10, decimal_places=2) pubdate = models.DateField() book_type = models.ForeignKey(BookType)
# 注意这个 是django自带的序列化 但是它不支持时间 小数等格式 ret = models.Book.objects.filter(con) print(ret) # queryset,[对象] from django.core import serializers data = serializers.serialize("json", ret) print(type(data),data)
# 字符串 这是通过 映射 取到值 """ """ # ret = models.Book.objects.filter(con).values(\'name\',\'book_type__caption\')# 列表里面以字典的形式 # #ret = models.Book.objects.filter(con).values_list(\'name\', \'book_type__caption\')# 列表里面以元组的形式 # # li = list(ret) # data = json.dumps(li) # print(data,type(data))