sql - Distinct elements in django model -


I am a Django novice and I wonder if there is a more efficient way to do the following tasks (at the database level) .

I have a model: 

  class.fu (models.Model): item = model.Intergrill () another_item = models.IntegerField ()   
 and want to get all the different values ​​of "item". 
 
 It is that I have done so far: 
 
  distinct = set (for row in [Row.item Foo.objects.all ()))  
 
 It's easy to understand But if I understand how Django works then the SQL query is not very efficient because it is something like this: 
 
  SELECT * FROM DB  
 
 When I only need: 
 
  choose items separately from DB  
 
 Any way to do it more efficiently? 
 
 
 
 
 
 You  different  section to  value  or < Want to use in conjunction with code> values_list  section? 
 
  different ,  value  and  values_list  are all there. 
 
 Then you can do this: 
 
  Foo.objects.values_list ('item', flat = true)  
 
 and It will return a list of items - match your  match to a different item related to  query.

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