Python自动化之django orm之Q对象

Python自动化之django orm之Q对象

什么是Q对象?

Encapsulates filters as objects that can then be combined logically (using& and |)

关联查询

Poll.objects.get(
    Q(pub_date=date(2005, 5, 2)) | Q(pub_date=date(2005, 5, 6)),
    question__startswith='Who')

AND AND

def ceshi(request):
    from app01 import models
    from django.db.models import Q
    conn = Q()  # 大Q对象
    q1 = Q()  # 小Q对象
    
    # 下面都是或的关系
    q1.connector='OR'
    q1.children.append(('id', 1))
    q1.children.append(('id', 2))
    q1.children.append(('id', 3))
    
    #这个q2也是小Q
    q2 = Q()
    q2.connector = 'OR'
    q2.children.append(('name', 'wo'))
    conn.add(q1, 'AND')
    print(conn)
    print('------')
    conn.add(q2, 'AND')
    print(conn)
    print(q1)
    a = models.User.objects.filter(conn)
    print(a.values())
    return HttpResponse('ok')

结果

(AND: (OR: ('id', 1), ('id', 2), ('id', 3)))
------
(AND: (OR: ('id', 1), ('id', 2), ('id', 3)), ('name', 'wo'))

AND OR

from django.shortcuts import render, HttpResponse
from django.core.exceptions import NON_FIELD_ERRORS
# Create your views here.

from django import forms
from django.forms import fields
from django.forms import widgets

class User(forms.Form):
    usertype = fields.ChoiceField(
        choices=[],
        widget=widgets.Select

    )

    def __init__(self,*args,**kwargs):
        super(User,self).__init__(*args,**kwargs)
        print(self.fields['usertype'])
        print(type(self.fields['usertype']))
    # print(dir())

def ceshi(request):
    from app01 import models
    from django.db.models import Q
    conn = Q()
    q1 = Q()
    q1.connector='OR'
    q1.children.append(('id', 1))
    q1.children.append(('id', 2))
    q1.children.append(('id', 3))

    q2 = Q()
    q2.connector = 'OR'
    q2.children.append(('name', 'wo'))
    conn.add(q1, 'AND')
    print(conn)
    print('------')
    conn.add(q2, 'OR')
    print(conn)

    a = models.User.objects.filter(conn)
    return HttpResponse('ok')

结果

(AND: (OR: ('id', 1), ('id', 2), ('id', 3)))
------
(OR: (AND: (OR: ('id', 1), ('id', 2), ('id', 3))), (OR: ('name', 'wo')))