分组 F查询 Q 查询

1 annotate
2 
3 # models.Publish.objects.annotate(a=Avg('book__price')).values('a')
4 
5 # models.Book.objects.values('publish_id','id').annotate(a=Avg('price')) {'pulish_id':1,'a':11.11}

F查询和Q查询

 1 from django.db.models import F,Q
 2 
 3 F  针对自己单表中字段的比较和处理
 4 models.Book.objects.filter(good__gt=F('comment')*2)
 5 models.Book.objects.all().update(price=F('price')+1)
 6 
 7 Q    &  |  非~
 8 filter(Q(xx=11)|Q(ss=22)&Q(oo=33))
 9 filter(Q(Q(xx=11)|Q(ss=22))&Q(oo=33))  &优先级高
10 filter(Q(Q(xx=11)|Q(ss=22))&Q(oo=33),name='dd')  

执行原生sql(了解)

1 models.Publish.objects.raw('原生sql')
2 
3 from django.db import connection
4 cursor = connection.cursor()
5 cursor.excute(sql,[1,])
6 cursor.fetchall()

展示sql的

1 models.Book.objects.filter(good__gt=F('comment')*2)
2 from django.db import connection
3 print(connection.queries)