python manage.py shell进入虚拟环境

>>>from firstApp.models import Topic,Comment

>>>from django.contrib.auth.models import User #save插入方法

>>>user=User.objects.get(username=‘xym‘)

>>>topic=Topic(title=‘four topic‘,content=‘this is the four topic‘,user=user)

>>>topic.save()

>>>comment=Comment(content=‘so bad‘,up=123,down=321,topics_id=topic)

>>>comment.save()

>>> user1=User.objects.get(username=‘xym‘)
>>> topic_2=Topic.objects.create(title=‘second topic‘,content=‘this is the second topic‘,user=user1)
>>> coment=Comment.objects.create(content=‘so good!‘,up=99,down=33,topics=topic_2)

>>> Topic.objects.get_or_create(id=1,title=‘first topic‘)
(<Topic: 1:first topic>, False)
>>> Topic.objects.get_or_create(id=1)
(<Topic: 1:first topic>, False)
>>> Topic.objects.get_or_create(id=3)
(<Topic: 3:three>, False)

>>> Topic.objects.get_or_create(id=4,title=‘four topic‘,content=‘this is the four topic!‘,user=user)
(<Topic: 4:four topic>, True)

>>> Topic.objects.all()
<QuerySet [<Topic: 4:four topic>, <Topic: 3:three>, <Topic: 2:second topic>, <Topic: 1:first topic>]>

>>> print(Topic.objects.all().query)#返回查询过程

>>> Topic.objects.reverse()
<QuerySet [<Topic: 1:first topic>, <Topic: 2:second topic>, <Topic: 3:three>, <Topic: 4:four topic>]>

>>> print(Topic.objects.reverse().query)
SELECT `firstApp_topic`.`id`,
         `firstApp_topic`.`create_time`,
         `firstApp_topic`.`update_time`,
         `firstApp_topic`.`title`,
         `firstApp_topic`.`content`,
         `firstApp_topic`.`is _online`,
         `firstApp_topic`.`user_id`
FROM `firstApp_topic`
ORDER BY  `firstApp_topic`.`create_time` ASC

>>> Topic.objects.filter(id__lte=3)
<QuerySet [<Topic: 3:three>, <Topic: 2:second topic>, <Topic: 1:first topic>]>

>>> Topic.objects.exclude(id__lte=3)
<QuerySet [<Topic: 4:four topic>]>

>>> Topic.objects.filter(id__lte=3).exclude(title__contains=‘tle‘)
<QuerySet [<Topic: 3:three>, <Topic: 2:second topic>, <Topic: 1:first topic>]>
>>> Topic.objects.filter(id__lte=3).exclude(title__contains=‘tle‘).filter(content__contains=‘first‘)
<QuerySet [<Topic: 1:first topic>]>

查询过程

print(Topic.objects.filter(id__lte=3).exclude(title__contains=‘tle‘).filter(content__contains=‘first‘).query)

SELECT `firstApp_topic`.`id`,
         `firstApp_topic`.`create_time`,
         `firstApp_topic`.`update_time`,
         `firstApp_topic`.`title`,
         `firstApp_topic`.`content`,
         `firstApp_topic`.`is _online`,
         `firstApp_topic`.`user_id`
FROM `firstApp_topic`
WHERE (`firstApp_topic`.`id` <= 3
        AND NOT (`firstApp_topic`.`title` LIKE BINARY %tle%)
        AND `firstApp_topic`.` content` LIKE BINARY %first%)
ORDER BY  `firstApp_topic`.`create_time` DESC

>>> Comment.objects.values(‘id‘,‘content‘)
<QuerySet [{‘id‘: 3, ‘content‘: ‘very good!!‘}, {‘id‘: 2, ‘content‘: ‘good!‘}, {‘id‘: 1, ‘content‘: ‘very good!‘}]>

SELECT `firstApp_comment`.`id`,
         `firstApp_comment`.`content`
FROM `firstApp_comment`
ORDER BY  `firstApp_comment`.`create_time` DESC

>>> Comment.objects.values_list(‘id‘,‘content‘)
<QuerySet [(3, ‘very good!!‘), (2, ‘good!‘), (1, ‘very good!‘)]>

SELECT `firstApp_comment`.`id`,
         `firstApp_comment`.`content`
FROM `firstApp_comment`
ORDER BY  `firstApp_comment`.`create_time` DESC